Genitopatellar Syndrome

In recent years there has been a rise in a new genetic disorder. The symptoms of the disorder are: an absence of a kneecap, a small scrotum, abnormal kidneys, facial defects, club feet, and mental retardation. A study was conducted on six boys and one girl of five different families. Two of the seven children were aborted with knowing their children had the syndrome. Three of the children did not survive but just a few years during adolescence and two of the children lived but suffered severe mental delay.

One of the main features from this condition is altered facial features. Those with the disorder often have a large, broad nose with a high nasal bridge. A small jaw bone is often noticed along with skewed facial features. The smaller jaw bone can be attributed to a smaller sized head.

There are numerous physical abnormalities that are displayed with the disorder. A common abnormality is the lack of a kneecap. Along with an altered knee, the children also suffered from club foot which occurs when the feet are not aligned with the body. Often times they are turned far inward until the feet would be nearly turned on their sides. One thing that can be easily noticed judging off physical attributes is that they often times have smaller hands than normal. Another physical defect is altered genitalia. In males the testicles can be shrunken to the point of little existence or the other defect is having either one or no testicles. For females, the clitoris is moved further to the front of the body and the labia or lips of the vagina are often enlarged.

The internal effects of genitopatellar syndrome vary but are often located with areas around the legs along with the physical deformity of the feet. As from the name of the disorder, those who are born with the condition are born without kneecaps. Yet the knee is not the only place for defects. Abnormalities to the hip bones can range in dislocation to proper orientation or flexion of the hips. If the children live old enough to ingest food, they often have troubles with swallowing. This disability can be attributed to hypotonia which is having low muscle tone or simply weaker muscles. Another internal effect is that of the kidneys. The children displayed dilated kidneys or are misshaped. Some of the kidneys from the patients also had cysts. Lastly, one symptom of the disorder is severe mental retardation. Of the two patients that lived beyond approximately one year, the retardation was severe enough to hinder them of independence and normal functioning.

The disorder is thought to be linked to chromosomes other than those that control sex and is recessively inherited. The parents of the children were examined to be healthy adults and did not interbreed within their family. The families were not related even though their children suffered the same effects. Genitopatellar syndrome is a crippling disorder than not only affects one physically but causes mental handicaps as well.

Cormier-Daire, Valérie. (2000). Genitopatellar syndrome: a new condition comprising absent patellae,

scrotal hypoplasia, renal anomalies, facial dysmorphism, and mental retardation. Journal

of Medical Genetics. Volume 37, Issue 7, 520-524.

Sara Puckett

Genetics of type 1 diabetes

Type 1 diabetes is a chronic disease in which there are high levels of sugar in the blood. While type 1 diabetes can occur at any age, it is most often diagnosed in children, adolescent, and young adults. Type 1 diabetes is a complex, multigenic disease. Nearly 40 years ago, the first reports of genetic association to type 1 diabetes were for the human leukocyte antigen region. Since then, researchers have not only been trying to pinpoint which alleles of human leukocyte antigen-encoding genes are responsible for type 1 diabetes association, but also which other genetic loci contribute to the type 1 diabetes risk. Human leukocyte antigen does not refer to a single genetic locus, but rather a region of the genome, containing less than 6543 unique allele sequences. There is also a strong association between type 1 diabetes and polymorphism in the promoter region of the insulin gene. Part of what makes sorting through human leukocyte antigen associations so difficult is the extremely large numbers of reported alleles at the human leukocyte genetic loci as well as differences in allele frequencies and haploid combinations among populations, incomplete penetrance of the human leukocyte antigen susceptibility loci, and epistatic interactions with other susceptibility factors. For some alleles of human leukocyte antigen, the risk of type 1 diabetes is determined by specific combinations of alleles, rather than by genotype. Multiple haplotypes are positively associated with type 1 diabetes, while many others are negatively associated. Specific genotypic combinations are also associated with increased risk, although still not the main cause. Maintaining a consistent nomenclature among scientists has been very challenging with the extreme polymorphism of the human leukocyte antigen-encoding loci. There has also been a dramatic increase in the number of reported human leukocyte alleles with new and better genotyping technologies, which adds to the challenges faced by modern scientists. There are dozens to thousands of alleles that exist for each human leukocyte antigen gene. In order to establish other genes in the human leukocyte antigen region as potential type 1 diabetes risk loci, scientists must first demonstrate an observed association in the human leukocyte region is a true disease susceptibility effect, and not only due to linkage disequilibrium. Currently, it is believed that type 1 diabetes results from an initial triggering event. This is followed by gradual autoimmune destruction of the pancreatic β cells, until the residual β cells are insufficient to meet the insulin demands of the body. Since the trigger of type 1 diabetes is unknown, the autoimmune process is usually undetected until the time of diagnosis. The rate of autoimmune destruction is unknown, and could vary among individuals. The end of the autoimmune process is marked by the destruction of pancreatic β cells by cytotoxic T cells. Even after almost forty years of research, human leukocyte antigen is still the strongest predictor of risk for type 1 diabetes, with reported odds ratios ranging from 0.02 to less than 11. However, the genetics of type 1 diabetes is more complex than any scientist could have predicted. Therefore, while scientists know quite a bit about the genetics of susceptibility to type 1 diabetes, more data is necessary to determine where the link is.

Works Cited:

Noble, Janelle A., and Henry A. Erlich. "Genetics of Type 1 Diabetes." PubMed Central. Cold Spring Harbor Perspectives in Medicine, Jan. 2012. Web. 13 Feb. 2012. .

Ashley Sisk

The Blue People of Troublesome Creek

Hematologist Madison Cawein, who traveled back and forth, from Lexington to Hazard, KY, explored rumors and legends of the blue people of the hills and hollows. He began his search at the local clinic and from there, explored all over the hills and creeks close by. The trait he searched for was the rumored blue people—no, not smurfs. These people were thought “to have a heart disease, lung disorder, or that simply their blood was closer to their skin.” After concluding that neither of these hypotheses were correct, Cawein did more investigation involving many blood tests. He originally suspected methemoglobinemia, a rare hereditary blood disorder that results in excess methemoglobin—a blue nonfunctional form or the red hemoglobin that carries oxygen to the body. Blue is the color of oxygen-depleted blood cells that you see in veins below the skin. Several causes of this could be abnormal hemoglobin formation, enzyme deficiency, or too much of a particular drug or vitamin. First, Cawein tested for abnormal or a deficiency of hemoglobin; the results were negative. He did some research that led to his new hypothesis of a diaphorase deficiency. Diaphorase is used by the body to break down methemoglobin into hemoglobin; if this is not present, methemoglobin numbers rise disproportionately in the blood giving it a blue tint. This doesn’t mean, however, that the individual is deprived of oxygen but strictly is a condition of pigment.

Cawein further explored the reason for this. He found it a recessive trait and is typically suffered from excessive inbreeding, or contiguous mating. The family tree he studied was that of Martin Fugate, an immigrant orphan from France. The pedigree that Martin made was extensive and displayed said inbreeding, which was common in the isolated area as there was few people in the area to begin with. Three families were mentioned: Fugates, Stacys, and Ritchies. It was only natural for a member of the family to marry “the girl next door” since choice was limited even if they had the same name…

To attempt to fix the embarrassing condition Cawein made 100 mg pills made of methylene blue which would hopefully reverse the blue effects, if only temporary. So the pill must be taken daily, as the methylene blue would be peed out. The study ended here. Cawein then focused on creating a pedigree, a chart displaying the family tree and a trait that is passed down. It is used to help trace back the origination of a gene, in this case Martin Fugate, the father of the Fugate clan, married Elizabeth Smith, a carrier of the trait. Martin was said to be blue thus passing the gene onto his seven children, four of which were blue. These children went on to pass the trait to the other two families as well as keep it in their own, marrying cousins. Once World Ward II rolled around the family began to spread out and marry others. Evidence of the blue gene would soon be lost to carriers of the trait and would be simply coincidence if they married another carrier unless they were distant family. Odds of that would be slim and highly unlikely.

This article interested me because I have family that live in Appalachia very close to Kentucky. I’ve heard stories about blue people but never really understood it or tried to do more research on it. I found it interesting because although the trait dispersed and the last remaining direct Fugate descendant died, the trait can still emerge. This trait was also found in Eskimos and Indians, which I also found very interesting.

By: Kara Ward

Cites:

• Cawein, Madison, Behlen, Charles H., Lappat, E. J., and Cohn, Jerome. Hereditary Diaphorase Deficiency and Methemoglobinemia. 1964. Archives of Internal Medicine. http://archinte.ama-assn.org/cgi/content/summary/113/4/578.
• Trost, Cathy. The Blue People of Troublesome Creek. 1982. Science Magazine, 82. http://www.indiana.edu/~oso/lessons/Blues/TheBlues.htm.
• http://topics.info.com/Who-were-the-Blue-People-in-Appalachia_171

Mutation Buffering

Each of us has come in contact with a person who has been taken captive by a harmful disease by no fault of their own but instead their adversity it at the hands of chance. We clearly see the detrimental effects mutations have on humans. Huntington’s disease and cystic fibrosis, for example, are familiar genetic diseases that affect humans in an array of severity. One person may have a mild case of cystic fibrosis whereas another individual suffers from the most severe case. Is this by chance? The research article, Trade-Offs and Environmentally Induced Mutation Buffering in Isogenic Caenorhabditis elegans, studied whether environmental stress changed the frequency of mutations’ harmful effects. Caenorhabditis elegans, abbreviated C. elegans, are nematodes or roundworms. The environmental stress levels of the organisms were increased by overexpressing the heat shock factor. The results of the environmental stimulus were that the harmful effects of mutations were lessened. For example, a generally lethal mutation, meaning deadly, among C. elegans resulted in a lethality rate of 17% that was normally 33%. Chaperone proteins were found to be a variable that affected the consequences of mutations. Environmentally induced stress resulted in the expression of chaperone proteins. Chaperone proteins are proteins that assist in the folding and unfolding of macromolecules. Chaperones decrease the likelihood of misfolding or the aggregation or grouping together of proteins. Therefore, temporary induced stress stimulus can promote mutation protection by increasing stress resistance.
The consequences of mutations vary individually. Hence, if a mutation is inherited, the affects the mutation will have on the individual depends on the chaperone levels within the individual and not the inherited mutation itself. The same holds true if chaperone levels were already higher in one individual than another without being induced, the individual with higher chaperone levels will have greater stress resistance. Chaperones were found to have a direct correlation with lifespan among C. elegans meaning, higher levels of chaperones resulted in a longer lifespan and the reverse also proved to be true.
Undoubtedly, all C. elegans could benefit from stress resistance in relation to susceptibility to mutations. However, stress resistance effects several other genes related to fitness. Fertility, for example is affected in that high stress resistance yields less offspring and low stress resistance yields more offspring. The organism C. elegans undergo diverse environmental conditions therefore their survival rate is increased by having both high and low stress resistance organisms within their environment. Misfortune
If the research conducted on round worms can be applied to human genetic diseases, then the importance of this study is clear. The ability to buffer the effects of mutations in humans would be a life changing discovery. Although the effects of mutations vary among individuals, the capacity to protect individuals from the consequences of mutations is predictable according to this study and its concepts may be applied to human genetics. This study was of interest to me because my healthiness is a mere grain of sand compared to the ocean of those suffering from the dire consequences of mutations. Any scientific step toward alleviating the effects of mutations is research worth reading, understanding, and applying.

Citation: M. O. Casanueva, A. Burga, B. Lehner, Science 335, 82 (2012); 10.1126/science.1213491.

Quanytta Johnson

Parkinson's Disease in the Amish Community

Parkinson’s disease (PD) is the second most common neurodegenerative disorder after Alzheimer’s disease, affecting approximately 120 per 100,000 individuals in the United States. Parkinson’s disease is a disease that affects the way a person moves. It occurs when there is a problem with certain types of nerve cells within your brain. These certain nerve cells make a chemical called dopamine. Dopamine sends signals to the part of the brain that controls movement and allows the muscles to move smoothly and do what you want them to. However, with Parkinson’s disease, the nerve cells break down. Without these nerve cells, the body can no longer produce dopamine. Therefore, a person with Parkinson’s disease has trouble with their movement. Parkinson’s disease is progressive, which means it gets worse over time. This usually happens slowly over a long period of many years. There are four main symptoms of Parkinson’s disease. This includes tremors, stiff muscles, slow movement, and problems with balancing and walking. Tremors in the body are usually the first symptom of Parkinson’s disease. The cause of PD is unknown, although older age and smoking habit appear to be established risk factors.

The article I chose is called “A Genome-wide Scan in an Amish Pedigree with Parkinsonism.” The researchers of this study wanted to identify the PD genes in an eight generation Amish pedigree with apparent autosomal dominant Parkinsonism with incomplete penetrance. Autosomal dominance is a gene on one of the non-sex chromosomes that is always expressed, even if only one copy is present. However, since it has incomplete penetrance, it means that even if the individuals have the genes that would express Parkinson’s disease, not all would express it.

So far, seven genes have been identified in familial PD cases: α—synuclein (PARK1, PARK4), Parkin (PARK2), UCH-L1 (PARK5), PINK1 (PARK6), DJ-1 (PARK7), LRRK2 (PARK8), and ATP13A2 (PARK9).

Individuals who were being screened had to go through an interview with a board of genetic counselors. They were screened for a history of encephalitis, dopamine-blocking medication exposure within one year before diagnosis, symptoms of normal pressure hydrocephalus, or a clinical course with unusual features suggestive of atypical or secondary Parkinsonism. Participants were also evaluated for a history of exposure to substances known or suspected to cause Parkinsonism, including heavy metals or pesticides. Individuals with a positive symptom history of PD as well as unaffected individuals were personally examined by a board-certified neurologist with subspecialty training in movement disorders. Participants were classified as affected, unaffected or unclear, using published diagnostic criteria based on clinical history and neurologic examination.

Affected individuals had at least two cardinal signs of PD (tremors, slow movement, or rigidity) and no atypical features of Parkinsonism. Individuals with unclear status had only 1 sign of PD, a history of atypical clinical features, or both. Unaffected individuals had no signs of PD.

The severity of signs and symptoms was evaluated by the Unified Parkinson’s Disease Rating Scale. To figure out the genotypes of the individuals, DNA samples were prepared from whole blood using standard methods and stored using a bar-coded system. The genomic screen was conducted using a preselected set of 364 markers conducted in multiplex sets of two to three markers per sample.

What they found in this screening is that there were some genetic factors for why this pedigree has PD, but there is also evidence of environmental factors causing this disorder. This surprised the researchers because they believed with the inbreeding in this type of community; Parkinson’s disease would be from a result of genetic factors.

I thought this article is interesting because my husband is half Amish. Also, both my husband and his father are showing signs of Parkinson’s disease. It helped me better understand what exactly Parkinson’s disease is and where he could possibly be getting the disease from.

Citation: Lee, S., Murdock, D., McCaughley, J., Haines, J. (2008). A Genome-wide Scan in an Amish Pedigree with Parkinsonism. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2764120/?tool=pubmed
Christina M. Strubhar

Genetics and Autism Spectrum Disorder

The article titled “Genetics and Mitochondrial Abnormalities in Autism Spectrum Disorders: A Review” gives a detailed overview of the research that has been done on genetics in relation to ASD or Autism Spectrum Disorder over the years. In this article autism is described by “The Diagnostic and Statistical Manual of Mental Disorders IV-Text Revised” as a complex neurobehavioral disorder characterized by deficiencies in social interaction, impaired communication skills and repetitive stereotypic behavior with onset prior to three years of age. In other words, people with ASD tend to have difficulty communicating and interacting with their peers and often enjoy repeating certain functions or behaviors. It must be made clear that ASD covers a very large range of severity from functioning ASD to very sever. Trying to find the cause of ASD or Autism Spectrum disorder is difficult and includes the role of the environment, the mitochondria and genes.

This article briefly looks into the role the environment plays in stating that family and environmental studies suggest that there are genetic risk factors present in ASD. Research suggests less than twenty percent of subjects with ASD can identify the cause of their disease to be linked to one gene or genetic factor. The rest of the subjects have many genetic causes and/or environmental factors that alter gene expression without changing the DNA sequence. This is referred to as epigenetic influences. Not only does the environment play a part in ASD but biological factors such as the mitochondria play a part as well.

The mitochondria play a large role in the cause of Autism Spectrum Disorder. The Mitochondria are cellular organelles and their function is to control energy production necessary for brain activity and development. Many studies have been done on the mitochondria and how it is linked with ASD and different types of result have been produced. For example, researchers Coleman and Blass proposed that mitochondrial energy production defects could cause abnormal brain metabolism in children with autism, leading to certain biochemical levels in the body to increase; these biochemical include lactate, pyruvate and alanine. Other researchers have found that many of their subjects with ASD often times had some sort of mitochondrial defect and even more researchers are finding mitochondrial abnormalities in young children with ASD. When learning about genetics and ASD we cannot only look at the mitochondria, we have to also look at how genes are a factor in causing Autism Spectrum Disorder.

There are certain nuclear genes that have been studies and correlations have been found between the defects of these genes and ASD. One nuclear gene that has been studied in particular is DNA polymerase gamma 1. Polymerase gamma 1 or POLG1 is an important enzyme in DNA processes; if there is any kind of mutation in this gene it will impact DNA replication as well as repair. Research has found that mutations of the POLG1 gene cause deletions of DNA genes. But what do these finding have to do with ASD? Autism Spectrum Disorder is linked to defects of a specific human chromosome region. The research mentioned before found a link between genes in the nucleus specifically on the chromosome region that ASD is found on. Therefor subjects with ASD were found to be more likely to have DNA over replication and/or deletions due to mitochondrial dysfunction.

To sum up, the environmental factors have to do with ASD but these factors are a bit more difficult to pin point and study. We know the role of the mitochondria and its defects have a relation to Autism Spectrum Disorder. Several studies have linked ASD to defects in the copying of DNA and interactions with nuclear genes. By looking at all three of these factors we hope to have a better understanding of what causes Autism Spectrum Disorder.

This article was very interesting to me and I really enjoyed writing about it. I decided to write about this article because I have a young cousin who has a form of Autism. I thought it would be interesting to learn what exactly caused him to get this disease. After reading the article I did learn a lot about what factors play a part in ASD. There is so much that goes into the causation of not only ASD but other diseases as well. I do not think I really understand how complex the human body is and how one tiny error can cause all kinds of problems, but this article helped me to see that.

cite: Dhillon S, Hellings J. A., Butler M. G. "Genetics and Mitochondrial Abnormalities in Autism Spectrum Disorder: A Review" 322-332 Current Genomics 2011, Vol. 12, No. 5

Posted By: M. Castaneda

The Influence of sex-linked genetic mechanisms on attention and impulsivity

There are sex differences in healthy individuals in a number of neurological domains such as awareness and brain structure. In this article, impulsivity and attention are tested on whether they are sexually dimorphic or if there is a phenotypic difference between males and females of the same species. Sex might dictate such abnormalities such as attention deficit hyperactivity disorder, autism, and addiction.
In this article, attention and impulsivity are examined to see if they are sexually dimorphic in healthy individuals and also individuals with psychiatric diagnosis. The focus of the discussion is on ADHD. It is said that 75% of ADHD diagnoses are in males. Attention is the ability to select from multiple stimuli, response, memories, and thoughts. It can be broken into 3 control systems: alerting, orienting, and executive. Alerting is preparedness and maintaining an alert state. Orienting is known as scanning or selection and is the ability to select information form multiple sensory stimuli. Executive attention is one’s focused attention. Impulsivity is action without forethought. It can be classified into two entities: impulsive action and impulsive choice.
Several studies have suggested that females have an advantage when it comes to executive attention and response inhibition. In contrast, males may outperform females in visuopatial selective attention, showing increased activation in the left hemisphere. When it comes to impulsive action, sex seemed to influence the function of brain regions associated with behavioral output. In this respect, males outperformed females in decision-making. Then the sex differences in attention and impulsivity were examined in neuropsychiatric disorders. This can be seen in ADHD. ADHD is a common neurodevelopmental disorder with a strong genetic basis, characterized by deficits in attention and extreme hyperactivity. They are diagnosed under 3 types: the inattentive subtype, hyperactive impulse subtype, and combined subtype. It has been shown that inattentive ADHD is prevalent among girls and hyperactive-impulsive and combined are more common in guys. It was then concluded that sex differences when it comes to this disorder may account for sex-specific differences in diagnosis. Females with ADHD had lower rating of hyperactivity, inattention, impulsivity, and externalizing problems, but have greater intellectual impairments and more internalizing problems. The evidence for sex differences in ADHD is very limited especially since there are differences in age, study sizes, and different treatment regimes. The sex-linked genes SRY, STS, and MAOA are the clear candidates for effects on attentional and impulsive behaviors. SRY gene is a Y linked gene, which encodes a protein. This protein then acts as a transcription factor in the developing fetus to induce gene expression changes. SRY influences cognitive attributes in males. The STS is X-linked and is key to attentional and impulsive operations. MAOA is also X-linked. The treatment for ADHD often involves inhibiting monoamine oxidase activity.
The evidence is strong that the sexes differ in their disorders of attention and impulsivity. There is also evidence that healthy males and females show differences in their attentional and impulsive profiles. The research in this subject however is limited. Identifying protective and risk factors encoded by sex-linked genes should help us to treat sex-biased disorders of attention and impulsivity.

article:http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3245859/?tool=pubmed

By: Kelleigh Jio

MicroRNAs Important Molecules in Cancer Research- Andrew Presgraves

Besides housekeeping genes, the expression of all other genes is mostly regulated through a complex mechanism that enables a cell type specific and time specific expression. Regulations can occur during each step of gene expression, e.g., during chromatin remodeling, transcription and translation, RNA transport, or on the post-transcriptional level. The main gene expression regulators are proteins or enzymes, e.g., histones, transcription factors, and polymerases. Gene expression can also be regulated by antisense or sense nucleic acids (Helene and Toulme, 1990). MicroRNAs (miRNAs) are a highly conserved family of small RNAs (17–22nt) that regulate the expression of their target genes usually on the post-transcriptional level by binding to complementary sequences on target messenger RNA transcripts (mRNAs) mostly resulting in gene silencing.(Leidinger, P)

Can we detect lung cancers earlier? Recent extensive scientific research has been conducted and currently no biomarkers exist to detect lung cancers at earlier stages. One scientific researcher has however been the first to relate miRNA expression to developments of lung caner. He found that miRNA can be found in skin tissues and this particular type is highly cell type specific and they reflect the developmental lineage and the differentiated state. MiRNAs can also be found in certain bodily fluids such as whole blood,serum, plasma, urine and cerebrospial spinal fluid, this being a much easier way to test for the miRNA. The miRNA profiles obtained from these fluid samples is very useful for the analysis and research of disease states this is especially useful when the disease does not originate from one specific cell source. How these miRNAs enter into the body fluids is still an unresolved question and is currently still being researched, but one possible explanation is cancer cells with metastatic potentials enter into the blood stream and release their cell content including miRNA material. MiRNAs packed into microvesicals or exosomes are entered into the bloodstream. In the bodily fluids test particularly saliva which contains blood cells, apoptic or detached epithelial living cells.Cell-free nucleic acids actively released by cancer and epithelial cells or inactively by apoptotic cells and micro-wounds have also been found in saliva. MicroRNAs play an essential role in lung development (Tomankova et al., 2010). Due to the different expression pattern in healthy lung tissue compared to lung cancer tissue it seemed legitimate to assume that aberrant miRNA expression may be involved in the onset of lung cancer. By microarray analyses of the miRNA expression in 104 pairs of primary lung cancers and corresponding non-cancerous lung tissues. From this a specific miRNA profile was discovered that contained more than 43 differently expresses miRNAs. This new research is definitely something that could put up a new defense towards cancers especially lung cancers which are so hard to detect in earlier stages, miRNAs have the potential to even be prognostics tools, focusing on the knowledge about miRNAs as tumor suppressor and activators for oncogenes, will lead to miRNA based therapeutic approaches.


Bibliography:

Keller, A., Leidigner, P., Meese, A. MicroRNAS Important Molecules in Lung Cancer Research. Pub Med- Frontiers in Genetics. Accessed 9 February 2012 //http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3263430/?tool=pubmed


Andrew Presgraves

Patterns with Genetic Disorders

Marking single nucleotides has often been used in order to identify genetic disorders and diseases. This has been useful however it has been suggested that identifying markers, called haplotypes, on chromosomes may be more effective. However due to a lack of technological advancement we are currently unable to identify exactly where the haplotypes are. On the other hand there has been enough advancement to lead to genome-wide association studies. Since there is a large quantity of tests only certain loci, places that were identified as markers, were able to pass the level set for usage. Yet all of the loci are still there and could be used to identify where the haplotypes are. There are more haplotypes than single nucleotides thus statistics is required in order to be able to map all of them. By examining patterns in the single nucleotides the scientists were able to discover where certain haplotypes were and deduce a pattern. This pattern was then able to be put to an equation very much like what one does in basic math; one plus one is two, two plus two is four and so forth. Granted the equation is more complicated, but that is due to the complicated matter of the material where the pattern exists. This formula, called a multi-locus stepwise regression allows for the identification of allele combination for genetic defects. So what exactly does this mean and what makes it so important? Genetic disorders arise from alterations of genes and how the alleles interact. By looking at a pedigree, a family tree which shows the pattern a genetic disorder within a family may have. This is a very useful technique however this is only based on information of the past and goes off the identification of a phenotype. If a phenotype, a physical manifestation of a gene, is not visible then one is unable create a pattern. There is also the fact that an individual may just be a carrier, not showing a disorder but having the possibility of passing it down to their offspring. Even now, we are still unable to fully map all of the potential genotypes, combinations of alleles which lead to the phenotype, within the human body. Though not by much, the possibility of finding a pattern of a genetic disorder within a gene itself has the potential for many outlets. One could start by identifying a pattern in all known genetic disorders, though tedious this would lead to the ability to identify exactly where the disorder arises from and the potential to combat them. Another route could be the ability of, instead of focusing on disorders; one could work to potentially map the human genome. Though just a possibility right now, the ability to find a pattern within a gene of a genetic disorder is a stepping stone, maybe the ability to stop a genetic disorder from arising before it even begins may arise eventually; or we may just become like Gattaca but that is for the future to decide.

Bibliography
Multi-locus stepwise regression: a haplotype-based algorithm for finding genetic. (2012, January 27). Retrieved Febuary 2012, from BioMed Central: http://www.biomedcentral.com/content/pdf/1471-2350-13-8.pdf

Halden Hoover

Formation and Repair of Tobacco Carcinogen-Derived Bulky DNA Adducts

Formation and Repair of Tobacco Carcinogen-Derived Bulky DNA Adducts
By Hang
This article is about how they are coming up with a way to rebuild the DNA function of active smokers and second hand smokers. To somehow prevent farer more relate cancer, and other diseases that cause of the death rise in the second hand and active smokers. They have found four different types of smoke that they have classified so far as: mainstream smoke (MSS), sidestream smoke (SHS), SHS mixture of about 85% of SSS and 15% of exhaled MSS, and thirdhand smoke (THS). They have been studying in the last 50 years to identify the different types of chemical toxicants in cigarette smoke which all react with DNA to form adducts. Also, of this I learn of that tobacco smoke provides a unique model for understanding the cause-effect or environment-gene relationship in smoking-related cancer development. It shown that cigarette smokers have higher levels of DNA adducts than nonsmokers. Found out that association between the in vivo levels of DNA adducts resulting from cigarette smoke and the occurrence of tobacco-related cancers in lings, head and neck, and bladder. There is a ranging of sugar damage cause from the tobacco carcinogens generate of the spectrum of the DNA lesions, and DNA crosslinks and strand breaks. The bulky DNA is formed by the covalent binding of those chemical carcinogens with large size. If unrepaired of the DNA adducts it may block replication and transcription. There is only a single DNA adduct that effectively block expression of a reporter gene. This does not just only represent a very early event by inducing specific genetic changes that are prerequisite to the initiation of cancer, but also occur during the continuum of the carcinogenic process. It can lead to nucleotide misincorporation that causes gene mutations. In the p53 gene is the more common mutation in lung cancers from smoker than nonsmokers. In one of the figure in the article show a diagram of how to correct repairs the tobacco carcinogens in the DNA so that no mutation can occur therefore any cancer. But the best way to avoid all of that of repairing of your DNA is to just quit smoking and avoid being around people that does smoke. The NER is a major pathway for the repair of various duplex-distorting bulky DNA lesions such as by PAHs. In studies of the last decade have revealed that if a DNA adduct is unrepaired or irreparable cells may use translesion DNA synthesis to bypass adduct the to ensure the continuum of DNA replication. Farer in the article we find out that in the last two decades considerable progress has been made in understanding the specificity mechanism of action, and in vivo importance of many repair enzymes and pathways. There are many excellent reiviews specifically related to the complete process as well as specific repair pathways that restore DNA to its normal state. There are also trying find a way to for that of leukemia to of that of the cell in the body and DNA to repair.
I pick this because it got my eye and it something different that of out here in the science word of life. To try to and repaired DNA and help to prevent farer more people to die of secondhand smoke and of the ones that smoke and of the dieseses that are cause by it also. Something new that us as humans are doing to keep people alive a little more longer. But I am a little confress on how we will be able to really get to the DNA and repair all threw DNA in a person? That is a question that will for ever be in the back of my head. That do we have the time to go threw a long strem of DNA a each person.

Racquita Dukes