Viability selection and genetic screening
20 Jul 2008 3:05am GMT Just a quick follow up to my post about genetic screening of embryos and subsequent implantation. The spontaneous abortion rate for humans is very high. Probably on the order of 50% of fertilized ova implant and complete to term. I've seen numbers all over the place. In any case, I assume many of these are chromosomal abnormalities. But I've also posted to data which strongly suggests that immunological incompatibilities between mother & fetus also play a role in spontaneous abortions and may...
HIV susceptibility, a "black" thing, not a Duffy thing?
19 Jul 2008 7:20pm GMT DARC and HIV: a false positive due to population structure?: The authors are aware of this potential confounder, and develop a measure of admixture based on 11 SNPs to include as a covariate in their regression. However, this measure is kind of weak, which I imagine in the sticking point for the skeptics in the Times article. If you have access to the supplemental information, take a look at it--several of these 11 SNPs are in the same gene, which means they're not independent, and several...
The Perfect BabyTM
19 Jul 2008 1:12am GMT Genetic Future points me to a Nature News story, Making babies: the next 30 years. He highlights this section: There's speculation that people will have designer babies, but I don't think the data are there to support that. The spectre of people wanting the perfect child is based on a false premise. No single gene predicts blondness or thinness or height or whatever the 'perfect baby' looks like. You might find genetic contributors but there are so many environmental factors too. The details...
R. A. Fisher and Epistasis
18 Jul 2008 6:34pm GMT David takes a slight detour in this Sewall Wright, series, R. A. Fisher and Epistasis: My next note on Sewall Wright will cover the exciting subject of the adaptive landscape. As every schoolboy knows, Wright considered epistatic gene interactions very important in determining the 'peaks' of the landscape. A sharp contrast is sometimes drawn between Wright and R. A. Fisher in this respect.... This is a preamble to a very long and dense post. If it interests you in the subject, I'd also...
Black and white twins & perils of Colored admixture
18 Jul 2008 8:26am GMT I was curious why an old Genetics and Health post, Twins with Different Skin Color Genes, was sending me many referrals today. Now I know, Two in a Million: Twins Born - One Black, One White: The twin boys, named Ryan and Leo, are the offspring of a mixed-race couple. The mother, Florence, hails from Ghana in western Africa, and dad, Stephan, is from Potsdam in Germany. "Ryan came first, and everything was as usual," said the hospital's doctor, Birgit Weber. "But when Leo was born, I...