Razib Khan One-stop-shopping for all of my content

January 7, 2012

PGD:2010s::IVF:1980s

Get ready for PGD, the acronym for preimplantation genetic diagnosis. We don’t really talk about “test tube babies” anymore. It’s “IVF,” and as American as apple pie (OK, perhaps as Israeli as falafel). Here’s the Ngrams result:


It’s just not that big of a deal anymore. But take a look at the order articles in The New York Times. There was a day that peopel were very worried about what “test tube babies” entailed. The end of the world as we know it? If that happened I don’t see anymore complaining.

The Globe & Mail in Canada has a very long piece on PGD, Unnatural selection: Is evolving reproductive technology ushering in a new age of eugenics? I do think it is ushering in a new age of eugenics, though it doesn’t go by that name. Many of the issues I’ve brought up on this weblog, such as the incentive for governments which fund national healthcare to take a deep interest in sifting through the range of future taxpayers and consumers of services, are explored. My basic instinct here is much more libertarian than most people. As a practical matter I’m rather close to a maximalist in terms of the amount of latitude I think parents should be given in selecting the nature of their offspring. But, I’m not a libertarian in an absolute philosophical sense, and I think a broader discussion in a society where the state and majority have coercive power over individuals is warranted.

There are two minor technical angles that I do want to bring up though:

- PGD seems to be ideally tailored already for people who marry their cousins. It would be relatively good at screening for the many recessive diseases which are common in the children of cousins. Also, it might even be able to reduce the fraction of runs of homozygosity through judicious selection. So, in the near future Muslim nations might be major consumers of PGD (Muslims as a whole are moderately anti-abortion, but they take a much more pragmatic line on these issues than the Roman Catholic church).

- PGD for trait selection runs into some statistical genetic difficulties. But, I wonder if perhaps PGD for decreased mutational load might be useful? With high coverage full genome scans could not one ascertain with good precision which genes have been subject to inherited or de novo deleterious mutations? It is generally assumed that loci where there is a major deleterious mutation masked by a normal functional copy still induce some fitness drag on the individual. The range in outcomes in siblings may be part of the natural variation in the mutational load. Parents may be tempted to lop off the asymmetrical-faced end of this.

July 14, 2011

Genzyme Oncology question

Filed under: Biotech,Genzyme Oncology — Razib Khan @ 10:32 pm

If anyone works at, or knows someone who works at, Genzyme Oncology in San Antonio, can you contact me? I have a few questions. Any of these methods will work:

May 31, 2011

Ban them! (including ancestry analysis)

Direct-to-Consumer Genetic Tests Neither Accurate in Their Predictions nor Beneficial to Individuals, Study Suggests:

Direct-to-consumer (DTC) genetic tests give inaccurate predictions of disease risks and many European geneticists believe that some of them should be banned, the annual conference of the European Society of Human Genetics heard May 31….

Here’s the abstract for the talk which argued that DTC companies don’t give the best disease risk estimates:

Objective: Direct-to-consumer (DTC) companies predict risks of common complex diseases on the basis of genetic markers. Given the low number of markers involved and their small effect sizes, it is unclear whether high-risk groups can be identified. We investigated the risk distributions generated by two DTC companies for 8 diseases.

Methods: We simulated genotype data for 100,000 individuals based on published genotype frequencies. Predicted risks were obtained using the formulas and risk data provided by the companies.

Results: The table presents observed and trimmed ranges of predicted risks. The two companies used different formulas to calculate risks. One company predicted risks higher than 100% for 5 out of 8 diseases, which for AMD concerned 1 in 200 individuals. Observed ranges were smaller for the second company, except for Type 1 Diabetes. Predicted risks higher than 50% ...

May 25, 2011

Biology to the masses

Filed under: Biology,Biotech,Personal genomics — Razib Khan @ 8:17 am

Josh Roseneau, when he’s taking time off from the evolution-creation wars, is poking around his own genome. Some sage advice:

On DNA Day, 23 and Me had a sale on their personal genomics service. They’d do their standard scan of your genome for free, as long as you paid for a year’s worth of their online subscription service.

For the price (nearly free up front, and a modest cost for the online community provided), my wife and I jumped on the deal. Since I got the results back two weeks ago, I’ve been exploring not only the services and information provided by 23 and Me, but the various other tools that individuals have started producing to help analyze and investigate this insight into my ubiquitous but invisible DNA.

My genome, for instance, revealed a genetic predisposition towards late-onset Alzheimers. The odds of getting Alzheimers are still quite small, but elevated because of this particular mutation to the APOE4 gene. This wasn’t a total surprise, given my family history, and as a healthy, young guy with a background in biology and biostatistics, it wasn’t hard for me to put that information into a context and move on. Down the road, I’ll ...

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