Top Genetic Findings of 2012

Take a moment to look back at the ten most interesting and significant genetic findings of 2012 or at least the ones that drew our attention.

In the last 12 months we’ve seen huge strides in genetic research giving us new insight into serious conditions such as Alzheimer’s as well as new treatments for cystic fibrosis. And in the last year scientists have made huge leaps in our understanding of the human genome itself with the culmination of a massive study of the so-called uncharted non-coding portions of our DNA – the ENCODE project. Researchers at 23andMe continue to contribute to some of these important findings with groundbreaking work on the relative importance of family health history versus genetics when determining disease risk and a new method to screen for the genetic risk for certain types of blood disorders. It’s been another great year of discovery and here’s our top ten.

1)    A Genetic Variant Protective Against Alzheimer’s Disease – The T version of rs63750847  – also known as the A673T variant in the APP gene – was associated with about five times lower odds of Alzheimer’s. While this is a very rare variant – only about one in 10,000 people of European descent have it – the research, done by the Icelandic company deCODE Genetics in association with Genentech, adds more insight into the development of the disease. Many mutations in the APP gene actually cause Alzheimer’s through an overproduction of beta amyloid protein in the brain (a hallmark of Alzheimer’s), but the protective variant appears to do the opposite, according to the study. New drugs built on this finding could help protect against Alzheimer’s, or even the mental ravages of normal aging. 23andMe does offer customers reports on their own Alzheimer’s risk based on the more common APOE variant, as well as a report on this protective APP variant.

2)    ENCODE Project Creates a Map of the Uncharted Areas of the Genome Much of the work in genetics has been focused on the areas in our DNA that code for proteins, but this is a very small part – just 1 percent – of our genome. The ENCODE project, which has enlisted more than 400 scientists over several years, is attempting to map the rest of it, the so called “dark matter” of the genome. What they’ve created is the foundation of a sort of encyclopedia of the functions of many of these uncharted areas of the genome. It’s a resource that will be used by many scientists in the years to come.

3)    Noninvasive Prenatal Sequencing – Two separate research groups reported within weeks of each other that they had successfully sequenced a human fetus and done so noninvasively. The breakthrough offers an opportunity for earlier prenatal screening than currently offered with amniocentesis or chorionic villous sampling (CVS) without the same risks for a developing fetus.

4)    New insights into a group of rare blood disorders known as MPNs – In less than a year, 23andMe recruited a 1,000-person cohort with a group of rare blood disorders known as myeloproliferative neoplasms, or MPNs. Within months of reaching that goal we began reporting our new findings. Among them were replications of known genetic associations with the disease as well as new ones including an association between these conditions and variants in the TERT and ATM genes.

5)    New Insights into Human Origins and Evolution – Several different studies highlight ongoing research on our early ancestors and the evolution of modern humans. Beyond the compelling tale of our early ancestors, the journey out of African and the intermixing with Neanderthals and Denisovans, the new research also gives us insight into the significance of rare genetic variants.

6)    Family Medical and Genetics Used Together to Predict Disease – 23andMe developed a model to show that both family history and genetic tests have strengths in predicting disease risks, but when used together they provide the best predictor for disease.

 7)    Older Dads’ Biological Clocks – For a long time prospective fathers could wile away the years without much worry about when to have kids, while prospective moms were constantly checking their ticking biological clocks. A study may turn the tables a bit, pushing men to think a little more about how long they wait to start a family. The study says that as men grow older the number of de novo mutations they pass onto their children increases, and preliminary studies suggest that the more de novo mutations passed onto a child the higher the risk that child could develop certain types of conditions, such as autism and schizophrenia. That said becoming a dad can actually be good for you. There’s evidence linking fatherhood to healthier hearts.

8)    Breast Size Matters, But Not How You Think – Researchers at 23andMe found that genetic factors influence breast size and that in turn these factors are connected to the genetics of breast cancer.

 9)    New Treatment for Cystic Fibrosis –  Early in 2012 the FDA approved ivacaftor (Kalydeco ®) as a new treatment for cystic fibrosis, one of the most common recessively inherited diseases. The drug developed by Vertex Pharmaceuticals Inc. is the first treatment that targets one of the underlying causes of cystic fibrosis – a specific genetic mutation – rather than its symptoms.

10)  Autism Study Reveals No Genetic Associations – It may be strange to point to a study that finds no genetic associations, but sometimes an absence of evidence can hint toward new routes of study. Cases of Autism spectrum disorders – which run the gamut from mild to severe impairment and include autism, Asperger syndrome and other disorders – have become increasingly common in the U.S. Why that is, is not so easy to discern. The lack of an association doesn’t mean that genetics isn’t important. In fact twin studies suggest that autism is at least moderately heritable, but it may be that genetic variations play a smaller role than rare mutations or copy number variation in the risk of a person developing autism.

  • Altorfer

    at 23andme

    You were able to find rs63750847 to be protective against alzheimer trough a Genomw wide association study?

    You weren’t able to find any genetic association for male homosexuality. But what if in some case homosexuality is caused through VERY RARE genetic mutation(SNP)? As in my case.

    Please let grow the study for sexual orientation in number of participant Because at the moment you only have asked 1100 male homosexuals for this study. In my opinion that’s too less persons. For this study you should have asked at least 5000 male homosexuals that was better. So please don’t break up the study of sexual orientation the next 4 or 5 years!

    Thank you

    Christian Altorfer

  • Kathleen Keane

    Your title regarding autism is misleading and should be immediately corrected……the title says NO link is found….but the content says it can be genetic. It is either way way or the other. As a medical editor — I say — fix this immediately. I would like to see genetic testing done for school-age children to help decipher what their disability is to help their education. Does autism show up in a DNA test? What about other developmental delays?

    • AJ


      The problem with genetics is that EVERYTHING has a genetic component, even how likely you are to catch a cold when exposed to the virus has a genetic component. So of course there is SOME connection to genetics, but a direct link has not been found. That doesn’t mean one may not be found in the future.

  • Barbara Ellison

    The title, “Autism Study Reveals No Genetic Associations” is not misleading to me..They found no association.. The content does not conflict with the title at all…The twin studies only “suggest” that autism might be heritable..but it is not proven..because no association has been found..More testing may show an association, or not. Time will tell.
    People can’t jump to conclusions as to what causes what is called autism…When conclusions are jumped to, then there is a large risk for faulty treatments that can be harmful..

  • shilo

    Um, I have a genetic mutation on my mthfr and I had read that autism was one of the problems associated with the mutation, and I actually have Asperger’s. Doesn’t seem correct.

    • Asperger’s is a type of autism.

      • Bill F.

        According to the DSM that is correct but that is only because there is a degree of overlap in symptomology. It may well turn out that there are different causes for these conditions. The original definition of Asperger’s was more distinct and the current definition seems to me to be driven by a desire to fit Asperger’s into the autism category. Classification is a way of simplifying the complex and too much concern with created classifications, especially when the root causes are unknown is not well founded.

  • I don’t understand #10 – it has already been shown that at least one genetic deletion/duplication (which can be inherited or de novo) can contribute to autism and autistic like behaviors – 16p11.2 deletion/duplication.

    • That’s nothing new – before the 16p11.2 results that were so widely publicized, I’d already found dozens of other autism-related genetic disorders from reading medical literature – 2q37 deletion, inverted 8p duplication, 22q13.3 deletion, active ring X syndrome, Smith-Lemli Opitz Syndrome, CHARGE Syndrome, and many, many others. I really don’t have a clue why the news picked out 16p11.2 disorders over all those other conditions that can cause autism.

      The thing is that a) there are literally hundreds of genetic disorders associated with autism, and b) the total proportion of autistics who have any diagnoseable genetic syndrome (including all those hundreds of conditions) is typically around 10% or fewer. We still don’t know any genes that could account for more than a tiny percentage of autistic people.

  • The “Autism spectrum” now effects 1 of every 100 American boys and many girls also, that is a CRISIS for this country, I don’t expect the answer to be easy to find and it has not been, science has not moved off of square one for a cure and that’s a tragedy for many. Many years ago I noticed many children of professional athletes, movie stars and others who were known steroid users had autistic children, obviously not all do, but something very seriously is effecting the development of these children once born on a genetic level, steroids, spermicides and all other environmental poisons and chemicals must not be overlooked when searching for the answer to autism.

    • I kind of find it offensive when people talk about the epidemic of autism as if the existence of people like me are some horrible crisis. We’re not as scary as you might think. The majority of autistic people are high functioning (autistic traits are on a bell curve, the more extreme the difference from normal, the rarer it gets). And even those who are low functioning, if given the right assistance, can contribute and live fulfilling and happy lives.

      Furthermore, it’s not accurate. Although diagnosis of autism is going up, that appears to be due to changing criteria. Criteria has broadened all along the spectrum. The milder autistics were not being diagnosed with anything in earlier times, while most of the lower functioning were diagnosed with either mental retardation or childhood schizophrenia.

      Childhood schizophrenia, in particular, has plummeted in frequency. It’s currently diagnosed in 1 out of 10,000 kids, whereas in the 1960s they had enough to fill schools with. Currently, it’s only diagnosed if there is clear, unambiguous evidence of hallucinations/delusions. Back then, it was diagnosed in children who were socially withdrawn with bizarre behavior, very often with no real evidence of psychotic features. In fact, many of these kids did not have enough language to report on such experiences. Back then, if the kid showed a period of normal development followed by regression, or if they showed any degree of social response, this meant they were not considered autistic.

      • I don’t think I would include you in the autism spectrum, if you feel you’re mildly autistic maybe you could help those that are severely effected by speaking and writing about helping them rather than trying to down play their condition.

        • I do help them. I volunteer with disabled kids on a regular basis, and I’m planning a career as a psychologist specializing in autism.

          Whether or not my autism diagnosis was accurate has nothing to do with the point I was trying to make. I could have made the same point just as easily as a psychologist or someone with autistic friends (some of whom are low functioning, by the way).

          You don’t know me or my issues. Verbal skills are a strength of mine – some of my weaknesses mean that I might not be able to live independently.

          So how about you reply to what I actually said, instead of attacking me?

      • SuperY

        Hey Ettina – in fairness to John, he is saying it’s a crisis when 1 out of 100 children may be unable to live independently. Most people wanting children (myself included) have strong preferences that said children not be eligible for diagnosis anywhere on the ASD spectrum. The reasons for this are practical as well as deeply selfish; we want our children to be normal, to fit in, to be attractive, to be successful, to mate, and to produce strong grandchildren so that our huge investment as parents is returned in some measurable way during our own lifetimes.

        Is this a bad thing? Not sure. But it really isn’t about you personally and John was not attacking you personally, though I can certainly understand why you feel that way. I’ve spent a lot of time with autistic individuals as well, as my wife volunteers and has also worked in the industry, and it’s hard to explain the powerful reaction I have to these individuals.

        If my child develops autism or other ASD I will be absolutely crushed. I have organized my life around minimizing the chances of this happening, and if it does anyway it will be an exceedingly difficult lesson for me.

        Best of luck to you, to John, and to all of us.

  • Kathleen Keane

    I want to know if genetic testing can be done by spit only or can it be done from a piece of hair from a deceased person.

    • ScottH

      We only test spit, but there are many labs that do DNA tests using hair samples.

    • blue

      Hair with the follicle (root) still attached will have nuclear DNA, just like spit. If the hair was cut or broken off, it will only have mitochondrial DNA. Everyone with a common maternal ancestor has identical mitochondrial DNA. It is only passed from mother to child.

  • Doc

    Hmmmm, would not being able to recognize the logical fallacy of ad hominem argument disqualify one from being considered normal?

  • Dr_Zinj

    The more we learn, the more we’re coming to realize that there’s more to inheritance than just DNA. Exogenic switching, and cellular cytoplasmic material inheritance are turning out to have almost as much to do with inheritance and development as DNA coding.