Monday, 3 December 2007

Could Dick Eastman be misleading us?



I was surprised to find myself doubting his opinion recently.






Hsien-Hsien Lei, PhD said...

Hi John, Thanks for linking to the video at I just want to point out that tracing the family history of hemophilia in a pedigree is somewhat different than doing the same for diseases such as diabetes because hemophilia is an X-linked disease that predominates in males who inherit the defective X chromosome from the mother. Because of this important distinction, it is possible to trace the spread of hemophilia through a family history. A prime example is hemophilia in the family history of European royalty.

As to not forgetting the importance of lifestyle factors in the development of disease, I totally agree with you. For complex diseases, such as diabetes, heart disease, and cancer, both genetic and environmental risk factors are critically important. However, there are monogenic diseases, such as hemophilia, in which one defective gene is all it takes for a person to develop a serious disease. In fact, over 10,000 human diseases are caused by a single genetic mutation.

I'm not very much involved in the genealogy community (although I find genetic genealogy absolutely fascinating) so I cannot vouch for Dick Eastman but based on what I've seen of his work, I wouldn't discount his credibility based on these specific statements you discussed.

Thanks again for visiting Eye on DNA! :)

Hsien-Hsien Lei, PhD said...

Oh, this is probably just a typo but I wanted to point out that we have 23 pairs of chromosomes including the sex chromosomes. So that's 22 autosomal chromosomes from each of our parents and 1 sex chromosome.