Naked Science Forum

Life Sciences => Physiology & Medicine => Topic started by: Jessica H on 06/04/2010 21:07:10

Title: Benefit to hemophilia?
Post by: Jessica H on 06/04/2010 21:07:10

Is there any known benefit of being a carrier (having one gene but not expressing the trait) of hemophilia?  It seems like the trait should have died out, unless there is some advantage?

Title: Benefit to hemophilia?
Post by: iko on 07/04/2010 15:40:43

Hi JessicaH,

nice question indeed!
I have two suggestions, but I'am not an expert:

- about 10% of hemophiliacs are from new mutations in FactorVIII or IX genes.

- in this world only 20% (maybe less) are treated.  Untreated hemophiliacs may become crippled and not necessarily die for a bleeding episode: they can reach the age of reproduction easily.

...any other ideas?

iko

Title: Benefit to hemophilia?
Post by: Enki on 11/04/2010 22:16:44

Not that we know of. It is continuously being weeded out of the population (because of high hemophiliac mortality), but reappears due to new mutations. It is rare.

Title: Benefit to hemophilia?
Post by: iko on 12/04/2010 14:33:14

Mortality in treated hemophiliacs increased in the 80's, unfortunately...because of treatment.

Quote

...
Impact of HIV Infection on Mortality of Hemophiliacs
As noted above, HIV has been detected in stored blood samples taken from hemophiliac patients in the United States as early as 1978 (Aronson, 1993). By 1984, 55 to 78 percent of U.S. hemophilic patients were HIV-infected (Lederman et al., 1985; Andes et al., 1989). A more recent survey found 46 percent of 9,496 clotting-factor recipients to be HIV-infected, only 9 of whom had a definitive date of seroconversion subsequent to April 1987 (Fricke et al., 1992). By Dec. 31, 1994, 3,863 individuals in the United States with hemophilia or coagulation disorders had been diagnosed with AIDS (CDC, 1995a).
The impact of HIV on the life expectancy of hemophiliacs has been dramatic. In a retrospective study of mortality among 701 hemophilic patients in the United States, median life expectancy for males with hemophilia increased from 40.9 years at the beginning of the century (1900-1920) to a high of 68 years after the introduction of factor therapy (1971 to 1980). In the era of AIDS (1981 to 1990), life expectancy declined to 49 years (Jones and Ratnoff, 1991) (Figure 6)....

http://www.thebody.com/content/art6649.html