There’s no doubt that blood saves lives.  According to the Red Cross, in the United States alone about five million people need a total of 14 million pints of blood each year.  That’s 38,000 pints every day.

But transfusions are not without their dangers.  Among them is transfusion-related acute lung injury (TRALI), a rare but potentially life-threatening condition that happens when there is a clash between donor and recipient blood.  TRALI is one of the major causes of transfusion-association deaths in the developed world.

New research, recently published in the journal Nature Medicine, suggests that many cases of TRALI are due to a difference at just one genetic variation between donor and recipient.  This finding could someday enable screening before a transfusion is done, allowing doctors to reduce the risk of TRALI. Continue Reading »

Tags: blood, blood donation, lung, Nature Medicine, Red Cross, TRALI

Warfarin (Coumadin®) is a blood thinner given to people at high risk for the formation of blood clots due to conditions such as deep vein thrombosis, heart valve disease or replacement, and irregular heart beat. The drug is also given to prevent recurrence of pulmonary embolism, heart attack and stroke.

If too little warfarin is prescribed, the threat of blood clots will remain. But if too much drug is given, uncontrolled bleeding can result. Add to this the fact that “too little” and “too much” can vary significantly between people, and it’s no wonder that complications from incorrect warfarin dosing are one of the most common reasons for emergency room visits due to adverse drug reactions.

In 2007, the FDA updated the labeling information for warfarin to include information about how variations in two genes, CYP2C9 and VKORC1, can impact a patient’s optimal dose of the drug.  But the FDA did not make specific dosing recommendations at that time.

Now the FDA has updated warfarin’s label once again, this time specifically saying that a “patient’s CYP2C9 and VKORC1 genotype information, when available, can assist in selection of the starting dose.”  Continue Reading »

Tags: CDER, CMS, Coumadin, FDA, warfarin

Cancer of the pancreas, which strikes more than 40,000 men and women in the United States each year, is an especially deadly malignancy.   There is no effective screening test for the disease and it is usually not detected until it has spread throughout the body.  The five-year survival rate is only about 5%.

Understanding more about the genetic factors that impact pancreatic cancer has the potential to improve prevention and early detection methods, and open new avenues for treatment.  In 2009 one of the first genomewide association studies of pancreatic cancer showed that a SNP on chromosome 9 was associated with risk of the disease.  This finding was not only one of the first strides into understanding the role of common variation in the disease, but it also added new evidence to the decades-long association between type O blood and lower risk for pancreatic cancer.

Now researchers from the same group have found variations in three other regions of the genome that also affect pancreatic cancer risk.  The results, based on an analysis of 3,851 cases and 3,934 controls of mainly European ancestry, were published online this week in the journal Nature Genetics. Continue Reading »

Tags: Nature Genetics, pancreatic cancer, Patrick Swayze, Randy Pausch, Ruth Bader Ginsburg

By Nick Eriksson, 23andMe Principal Scientist, and Lizzie Dorfman, Parkinson’s Research Project Manager

Less than a year ago we announced the launch of the 23andMe Parkinson’s Research Initiative. Since then, we have built one of the world’s most useful resources for studying the genetics of Parkinson’s disease. This past December we had meetings with the National Institutes of Health, FasterCures, pharmaceutical companies and several key Parkinson’s geneticists to discuss our research. The feedback was unequivocally positive. We are thrilled by the progress we’ve made and wanted to make sure to publicly share some of our most significant accomplishments to date, as well as a preview of what is to come.

So far, more than 3,500 people with Parkinson’s disease from 49 U.S. states and 17 countries have submitted saliva samples for genetic analysis and carefully answered more than 30,000 online surveys to help with our research. Our genetic database now includes many important subgroups of Parkinson’s patients, each presenting a tremendous opportunity for current and future research. These include a large group of people with early-onset Parkinson’s (≤50 years old at diagnosis), carriers of extremely rare mutations that are known to strongly predispose a person for the disease, and people with a family history of Parkinson’s with no known cause. We’ve also had an incredible response from our other communities: more than 8,000 people without Parkinson’s have taken our Parkinson’s surveys so that they can be included in our studies as crucial control subjects. Continue Reading »

Tags: community, FasterCures, GBA, LRRK2, MAPT, Michael J. Fox Foundation, NIH, Parkinson's Disease, PatientsLikeMe, SNCA, surveys, The Cure Parkinson's Trust, The National Parkinson Foundation, The Northwest Parkinson's Foundation, The Parkinson's Institute

Researchers have identified another region of the genome associated with childhood asthma, a condition that affects more than seven million American kids.

Analysis of DNA from about 1,700 children with asthma and 3,500 controls, all of European ancestry, identified several genetic variations on chromosome 1 associated with the risk of developing asthma.  Many of these same SNPs were then also found to be associated with risk for asthma in a sample of more than 1,600 African American children with asthma and 2,045 controls.  All of the newly identified SNPs are located near the gene that encodes DENND1B, a protein known to be involved in the body’s response to foreign particles.

“Many of these particles are well-known triggers of asthma.  In asthma, patients have an inappropriate immune response in which they develop airway inflammation and overreaction of the airway muscle cells,” explained Hakon Hakonarson, director of the Center for Applied Genomics at The Children’s Hospital of Philadelphia and the senior author of the study, in a press release. Continue Reading »

Tags: African American, asthma, DENND1B, European, New England Journal of Medicine

As shown in these ancestry paintings from 23andMe, the proportion of African DNA can vary widely for African Americans.

A recent study led by Carlos Bustamante of Cornell and Sarah Tishkoff of the University of Pennsylvania has shown that genetically speaking, African American can mean a lot of different things.

The researchers and their co-workers analyzed DNA data from 365 African Americans, 203 West Africans from 12 different countries, and 400 Europeans from 42 countries.  Their results, published in the Proceedings of the National Academy of Sciences, show that the average amount of DNA in an African American’s genome that could be traced back to West Africa was about 77%, but ranged from as little as one percent to as much as 99%.

These findings have important implications not only for understanding the ancestry of African Americans and the history of human migrations, but also for medical treatment.

“That some individuals who self-identify as African American show almost no West African ancestry and others show almost complete West African ancestry has implications for pharmacogenomics studies and assessment of disease risk… caution should be used in prescribing treatment based on differential guidelines for African Americans, ” the authors write. Continue Reading »

Tags: Africa, African American, pharmacogenomics, PNAS

Using a research method very similar to the one used in 23andMe’s Global Similarity advanced view feature, researchers have discovered that most of the embryonic stem cell lines currently studied by researchers are derived from European and Middle Eastern populations.  Only two out of 47 were derived from egg and sperm coming from people with East Asian ancestry.  None of the embryos had genetic makeup indicative of recent African ancestry.

“Embryonic stem cell research has the potential to change the future of medicine,” said Sean Morrison, director of the University of Michigan Center for Stem Cell Biology and one of the study leaders in a press release.  “But there’s a lack of diversity among today’s most commonly used human embryonic stem cell lines, which highlights an important social justice issue.”

The researchers analyzed the stem cells using a SNP chip much like the one used by 23andMe for its Personal Genome Service.  The genetic data of each stem cell line was then compared to the DNA of a set of publicly available reference individuals from 63 populations around the world. Continue Reading »

Tags: diversity, global similarity, stem cells

In 2009, we added six tools to 23andMe Labs, our technology sandbox where we showcase experimental features. In case you haven’t played around with them yet, here’s a brief review:

Health Labs

Reynolds Risk Score
This tool calculates a 10-year risk for heart-attack using information including cholesterol and blood pressure.

ABO Blood Type
There actually are more than 25 different blood groups that go into determining your particular “type,” but you’re probably most familiar with the blood group determined by the ABO gene. This is the gene that determines whether you will be type O, A, B, or AB.

Genetic Weight Calculator
See how much of your weight you can blame on your genes (not your jeans)!

Ancestry Labs

Haplogroup Tree Mutation MapperThis feature shows you which particular mutations in a person’s mitochondrial DNA (maternal ancestry) or Y chromosome (paternal ancestry) were used to determine their haplogroup assignment.

Family Inheritance: Advanced
Compare your DNA, bit by bit, to see what segments you share with close and distant family.

Native American Ancestry Finder
Search for evidence of Native American ancestry in a person’s genome. Continue Reading »

Tags: ABO, Family Inheritance, Haplogroup, Labs, Native American, relative finder, Reynolds Risk, Weight

In our last post we highlighted a few of the coolest (in our opinion!) health-related developments of 2009.  But human genetics isn’t all about disease.  Here are a few more favorites:

The Romanovs

2009 saw the identification of the remains of the missing members of this Russian royal family, as well as identification of the mutation that caused the hemophilia that plagued their youngest son.

Leaving No Stone Unturned: DNA Analysis Confirms Identities of Missing Romanovs

Researchers Discover the True Identity of the “Royal Disease”

The Celtic Fringe

The genetics of adorable little critters helped scientists understand the prehistory of the British Isles.

Life on the Fringe: Shrews and Voles Reveal Clues to British Prehistory

Link Between Australian Aborigines and India

Scientists discovered mitochondrial DNA markers shared by isolated tribes in India and native Australians…and nobody else.

Direct Genetic Link between Australia and India Provides New Insight into the Origins of Australian Aborigines Continue Reading »

Tags: 2009, Aborigines, Africa, ancestry, dogs, highlights, Romanovs, Royal diseas, voles

Today we’re going to look back at some of the health-related Spittoon highlights (a completely subjective list!) of 2009.

Hepatitis

Millions of people worldwide are chronically infected with some form of hepatitis virus, putting them at risk for cirrhosis and liver cancer.  In 2009 several studies identified genetic factors that influence susceptibility to hepatitis and response to treatment.

SNPwatch: Immune System Variations May Determine Susceptibility To Chronic Hepatitis B Infection

SNPwatch: Genetic Variation Predicts Hepatitis C Treatment Success

SNPwatch: More Evidence That Genetic Variations are Important for Hepatitis C Infection and Treatment

Melanoma

A study published in March offered insight into why melanoma, a rare but potentially deadly form of skin cancer, is more common in women under 40 than men in the same age group.

SNPwatch: Genetic Variation May Explain Why Young Women Are At Greater Risk For Melanoma Compared to Young Men

Alcohol Flush and Esophageal Cancer

Also in March, researchers issued a warning to physicians about the connection between “alcohol flush” and esophageal cancer. Continue Reading »

Tags: 2009, health, highlights, SNPwatch