A new study failed to provide answers after pursuing a genetic explanation for why one identical twin developed multiple sclerosis while the other stayed healthy.  Researchers created complete genetic blueprints for a pair of  identical twins, looking for differences that might explain why one developed multiple sclerosis and the other did not. According to researchers there were no traces of a discrepancy in the twins’ DNA.  Scientists found no smoking gun when they compared amount of gene activity between the twin with multiple sclerosis and the twin without. The results appear in a study published on April 29 in Nature.

According to Stephen Kingsmore, a geneticist at the National Center for Genome Resources in Santa Fe, N.M., and leader of the new study, “We looked under a lot of rocks and we found no differences that we could replicate.” Kingsmore went on to say that the findings “points to some novel environmental trigger that must be very important to the disease. We don’t know what it is.”

This study was small; it examines only three pairs of identical twins and  one type of immune cell known to be involved in multiple sclerosis. A telling difference between sickness and health might be found in other types of cells, says Esteban Ballestar of the Bellvitge Biomedical Research Institute in Barcelona, Spain.  Ballestar went on to say, “They are closing a door here, but I think, perhaps, the door should be open.” Multiple sclerosis is a disease where the immune system attacks and damages the myelin sheath that helps speed electrical communication between nerves, this is the equivalent of scraping the coating away from an electrical wire. The damage results in pain and symptoms such as loss of coordination and vision.

In the study, Kingsmore and his colleagues determined the entire genetic makeup of the immune cells called T cells from the female twin who had developed multiple sclerosis at age 30 and from her twin who had remained healthy. It was important that the twins were now old enough that the healthy one is not likely to develop the disease.

Identical twins share the same genetic makeup (it is believed that they have identical DNA), and the researchers confirmed that both women carried variants of genes already known to increase the risk of getting multiple sclerosis. Scientists had thought that maybe the sick twin had developed an additional mutation in her DNA that finally triggered the disease. But the team found no such mutations.

I just came across an article distributed by the Slate discussing the above topic. This brought my thinking to the use of DNA and the idea of anonymity in general.

DNA testing makes them easy to trace
By Rachel Lehmann-Haupt Last Updated Monday, March 1, 2010, at 9:36 AM ET

When Donor 3066 signed up with the California Cryobank, he offered some basic information about himself on a piece of paper: that he had a BA in theater; that his mother was a nurse and his father was in the Baseball Hall of Fame; that his birthday was Sept. 18, 1968. He made it clear that he didn’t want to be found by signing a waiver of anonymity…

Donor 3066 was being sought out by Michelle Jorgenson, a 39-year-old waitress from Sacramento, Calif., whose daughter, Cheyenne, was born in 1998.  When her daughter turned 5, Jorgenson joined the Donor Sibling Registry and began searching for other mothers and donor offspring who used Donor 3066. She was concerned because her daughter was sensitive to sounds and walked on her toes, and she wanted to know if other half-siblings were displaying similar behavior. Through the registry, she met a number of other mothers and half-siblings. She discovered that two had autism and two others showed similar signs of sensory disorder…

Jorgenson began her search by approaching a mother in her group with a son named Joshua and suggested he do a cheek swab so she could explore his paternal roots through a Y chromosome test. The mother agreed. Through the test, Michelle learned about some of Joshua’s genetic markers. A few weeks of searching on the Family Tree DNA Web site using these markers led to two families with matching DNA. Through one of the families, she met a woman who mentioned that she found the obit of a relative who was a former baseball manager, and three children were listed. Michelle suspected that this might be her donor’s father, so she looked up the phone number of his listed son. When Michelle called the number, the deceased man’s son answered the phone. She began to ask him questions: Was your father in the Baseball Hall of Fame? Were you born in Illinois? Did you ever donate sperm? When the man said yes, she asked him if his birthday was Sept. 18, 1968. When he answered yes, she burst into tears. “You’re the biological father of my daughter,” she said. He was shocked but agreed to talk to Cheyenne on the phone—and eventually allowed the two to come visit him in Los Angeles.

Although in this case there appears to be a happy out come for all parties this is not always the case.  What about the request for privacy that Donor’s sign up for when they choose to remain anonymous?  Is that even something that clinic should offer since there is no guarantee that the donor can’t be found?  What are the options for men who do become donors?  There are many questions that are raised in this article and very few answers, partly because technology is growing at such a fast rate and party because it appears in the article many clinics are ignoring this issue of privacy.  Let us know what you think about this issue.

Equinome, a company founded on research conducted at University College Dublin, just announced their new test to predict how horses will preform for racing. Testing will cost 1000 Euros per horse tested. Equinome’s test looks at the gene responsible for muscle mass development.

Muscle growth is governed by myostatin, a protein that determines whether an animal has compact muscles tuned for rapid sprints or a leaner body suited for endurance. There are three possible combination at this specific genetic marker. This test is not designed to identify how good a horse is likely to be, but rather what it will be good at.

According to Equinome, the three genetic combination that are possible are C:C, C:T and T:T.  A C:C horse is likely to be a fast, early maturing horse that performs well as a two-year-old, while a C:T horse has a mixture of speed and stamina and is the most versatile in terms of distance, and a T:T horse is best suited to races greater than 1 mile that require stamina.

Horse Genome Project coordinator Ernest Bailey of the University of Kentucky, Lexington stated that breeders have adopted genetic tests for paternity, coat color, and diseases but that performance prediction is new ground.

Equinome – The Speed Gene

I just came across an article distributed by WebVet announcing the above topic. This brought my thinking to  pets health in general.

By Claire Douglass for WebVet
Reviewed by Amy I. Attas, V.M.D.
All content on WebVet is reviewed annually by Vets to guarantee its timeliness and accuracy.
Article last reviewed – 8/1/2009

Some household cleaning products are loaded with chemicals, and can be harmful to your pet after prolonged exposure. Today, rates of canine cancer are increasing, following the same trend of rates of human cancers, which has caused researchers to look more closely at a shared environmental pathogenesis.

We are not immune to airborne toxins in the home. According to a 1992 U.S. Environmental Protection Agency publication “Targeting Indoor Air Pollution,” the air inside the typical home is an average of 2-5 times more polluted than the air outside, and in extreme cases, it can be up to 100 times more contaminated – largely because of household cleaners and pesticides.

According to the EPA more than 50 percent of indoor pollution is a direct result of household cleaning products. Pets and their owners are all vulnerable to the effects of perpetual exposure to the chemicals in these products.  The risks that people face being exposed to cleaning products increases with duration of exposure.  Stay at home or people who work at home have a reported 54 percent increased risk of cancer pets and companion animals are at even greater risk due to their faster metabolisms and smaller lungs. Pets process these chemicals at a faster rate and absorb more of these toxins into their bloodstreams as they breathe them in more rapidly.

According to the Morris Animal Foundation, an initiative to research and cure canine cancer that is endorsed by the Children’s Oncology Group, Animal Cancer Foundation, MIT/Harvard (Broad Institute), and the Mayo Clinic, one in four dogs will die of cancer. Cancer is the No. 1 cause of disease-related death in dogs over the age of two. The National Cancer Institute, the global leader in human cancer research, has included the study of cancer in dogs within its Comparative Oncology Program since 2003.

There are solution to this issue.  There are many affordable lines of organic cleaning products available at most grocery stores, as well as countless books and articles on making one’s own effective household cleaners for far less than the cost of conventional cleaning products.  I like apple vinegar mixed with water because it smells fresh and can be used on any surface as well as cutting through residue and lingering smells.

By using the numerous organic cleaning products now so readily available, or by saving money and easily making your own cleaning products, both pet and owner can breathe easier and live healthier lives.

Web Vet

Reported in the December issue of Molecular Cancer Research, a journal of the American Association for Cancer Research; researchers at the University of Florida have been able to just just a fraction of the normal dosage of a highly toxic, debilitating chemotherapy drug to achieve even better results in the fight against colon cancer cells.

Scientist say that more research is needed before the therapy can be tested in patients, but the discovery in human colon cancer cell lines and mice with established human tumors suggests that the addition of a small molecule to the cancer drug Temozolomide disrupts repair mechanisms in a type of tumor cells that is highly resistant to treatment.

Satya Narayan professor of anatomy and cell biology at the college of Medicine and a member of the University of Florida Shands Cancer Center said that, “This is very important because aside from aggressive surgery with possibly chemotherapy, there are no specific treatments for colon cancer. The recurrence rate for this type of cancer after surgery is very high, about 30 to 50 percent, and there is an urgent need to develop new approaches to manage this deadly disease.”

The National Cancer Institute estimates there will be about 106,000 new cases of colon cancer in the United States in by the end of 2009. It is the second most common cause of cancer-related death in both men and women in the Western hemisphere.

Colon cancer forms in the large intestine and survival rates vary according to how soon the cancer is diagnosed and the treatment is started. The challenge of treating patients is that colon cancer is not a single disease but an array of disorders with distinct molecular mechanisms, with one type being quite proficient at repairing the DNA damage inflicted by the drugs currently used to treat the disease.

Narayan’s research team evaluated more than 140,000 small molecules, finally arriving at a tiny molecule that precisely blocks the ability of cancer cells to recognize and repair the DNA damage inflicted by Temozolomide, or TMZ. Narayan said, “Our idea was if you induce DNA damage (with TMZ), and at the same time block cell repair, you can synergize toxic effects to the cancer cells. We hope that with this combination treatment we can reduce the tumors drastically and expand the lifetime of patients much longer than is currently possible.”

TMZ is commonly used against certain types of brain cancer. It works by damaging the DNA of the cancer. By combining TMZ with the small molecule, Narayan’s team was able to disable the colon cancer’s ability to manufacture repair enzymes.

The UF researchers effectively used an amount of TMZ that is about 10 times lower than recommended in its studies of mice with human colon cancer tumors. According to Narayan, if only about one-tenth as much TMZ is needed to kill cancer cells, it will be possible to use lower doses of a drug that creates a great deal of adverse side effects, a partial listing of which includes anxiety, back pain, breast pain, constipation, cough, diarrhea, dizziness, drowsiness, dry skin, hair loss, headache, joint pain, loss of appetite, mouth sores, muscle aches and nausea.

“By using these strategies we can predict that disruption of DNA repair by small molecules can bypass drug resistance factors and dramatically reduce side effects caused by toxic doses of TMZ,” Narayan said.

More study is needed before the combination can be tested in patients, but Narayan believes that TMZ can be combined with the small molecule in a single dose in pill or capsule form.

Sankar Mitra, Ph.D., a professor in the department of biochemistry and molecular biology at the University of Texas Medical Branch in Galveston, who did not participate in the study, said that, the research demonstrates that it is possible to sensitize colon cancer cells to TMZ more broadly than is now possible — a benefit of particular importance to patients with cancers that are as varied as colon cancer. “This could be the start of other small molecule inhibitors”

Sankar Mitra also noted that the therapeutic molecules were selected through sophisticated analysis of the structure of tens of thousands of potential small molecules from the National Cancer Institute database. The computer-based process, which can suggest likely cancer therapeutics within hours, replacing manual analysis which would normally have taken weeks or months.

Robert W. Sobol, Ph.D., an assistant professor of pharmacology and chemical biology, and human genetics, at the University of Pittsburgh Cancer Institute said that, “There have been a multitude of studies suggesting that inhibition of DNA polymerase beta would enhance chemotherapeutic response. However, potential inhibitors have been challenging to identify and most have proven to be non-specific and/or non-selective. The compound identified by Dr. Narayan appears to be the first in what I expect to be a growing list of DNA polymerase beta inhibitors that have clinical potential.”

The research was supported by grants from the National Cancer Institute of the National Institutes of Health.

Science Daily

A blood test that can determine the gender and genetic abnormalities in a unborn baby as early as five weeks has proven to be successful according to Dutch researchers.  The researchers claim that the test has almost 100 per cent accuracy in determining the fetus’s gender.

The blood test uses the mother’s plasma to extract Genetic information about their unborn baby.  The test can be used to determine if the unborn baby carries specific genetic abnormalities, such as muscular dystrophy, this test can be conducted shortly after conception.

Currently, testing for genetic abnormalities and gender cannot be carried out until at least 9 weeks and as late as 24 weeks.  The current methods of testing are either through a Chorionic Villus Sampling (CVS) or an Amniocentesis.

Chorionic Villus Sampling (CVS) is a medical procedure conducted by an OBGYN that is typically performed between 9 – 13 weeks gestational age, which is often mistakenly referred to Chronic Villus (or Villi) Sampling. CVS is a vaginal procedure that removes a very small portion of the placenta.

Amniocentesis is a medical procedure conducted by an OBGYN that is typically performed between 14 – 24 weeks gestational age. The amniocentesis procedure involves insertion of a needle into the womb and drawing out approximately 10cc’s of amniotic fluid, which surrounds the unborn baby.

Professor Michael Chapman, head of women’s and children’s health at the University of NSW, said that this new testing method was the “holy grail” of research.  “Scientists have been chasing this for about 25 years,” he said. “The biggest advantage of this in a wanted pregnancy is there is no risk of miscarriage during testing.”

The research team from the University Medical Center, in The Netherlands, used the test on 200 women. Only in 10 cases could the gender not be determined.  The procedure works by taking a sample from the mother’s blood plasma and extracting fetal DNA, which circulates in the mother’s blood. Looking for a specific gene sequence, doctors can then determine if the baby is a boy or a girl and is a carrier of specific disorders.  In most cases, the test will be performed on a seven-week-old fetus.

But Australian obstetricians warn the medical breakthrough is unlikely to be used in Australia because it could be used for gender selection and due to “ethical and moral” dilemmas.

The test did not address the fact that fetal DNA that is found in a mother’s blood can be from previous pregnancies even years later.  The research have not address how to determine if the DNA is from the current fetus.  While their are some DNA testing companies that have offered to use “simple” blood test to determine paternity for several years.  These test can often be unreliable.   While this new test promise great answer at no risk there are still some very big questions that haven’t been answered.

News.com.au

Classic autism strikes boys four times more often than girls, with the inclusion of milder variations (Asperger syndrome) boys are ten times more likely than girls to be diagnosed than girls.

UCLA Scientists link genetic variant to autism risk. This discovery may explain the gap in autism cases between boys and girls. Dr. Stanley Nelson, professor of human genetics at the David Geffen School of Medicine at UCLA and his team narrowed their research on a region of chromosome 17 that previous studies have tied to autism. In that region they discovered a variant of a gene (a gene that is essentially the same as another, but has mutational differences) called CACNA1G. Dr. Stanley Nelson and his team looked at the DNA of 1,046 members of families with at least two sons affected by autism for common gene variants.

According to Dr. Stanley Nelson, “We wanted to identify what was happening in this region of chromosome 17 that boosts autism risk. When the same genetic markers kept cropping up in a single region of the DNA, we knew we had uncovered a big clue.”

The researcher team traced the genetic markers to CACNA1G. CACNA1G helps move calcium between cells. They discovered a common variant that appears in the DNA of nearly 40 percent of the population studied.

“This alternate form of CACNA1G consistently increased the correlation to autism spectrum disorders, suggesting that inheriting the gene may heighten a child’s risk of developing autism,” Nelson said, but he emphasized that it cannot be considered a risk factor on its own. “This variant is a single piece of the puzzle,” he said. “We need a larger sample size to identify all of the genes involved in autism and to solve the whole puzzle of this disease.”

This study was funded by the National Institute of Mental Health and Cure Autism Now. The DNA samples were provided by the Los Angeles–based Autism Genetic Resource Exchange (AGRE).

For more information see:

UCLA Newsroom