2007-03-27 10:48:06 · 4 answers · asked by bettyboop 1 in Health ➔ Diseases & Conditions ➔ Infectious Diseases
One of your parents, it's a mutated copy of the gene that makes the beta chain of hemoglobin.
If you mean where did it come from evolutionarily, it's not known, though it's been speculated that there is a survival advantage in carriers of the trait in an increased resistance to malaria compared to people with two normal alleles of the gene.
2007-03-27 10:55:57 · answer #1 · answered by The Doc 6 · 1⤊ 0⤋
It is a recessive genetic trait, where there is a subtitution to the amino acid in the 6th postition of the hemaglobin chain.
because it is recessive, there are a few way for an offspring to either have the disease or the trait. For the most part, if both parents have the trait the offspring has 2/3 chance of developing the trait and 1/4 for having the disease.
S = normal s= disease SS=normal, Ss trait, ss disease
need 2 gene for each offspring
mom______S s
D__S_____SS Ss
a
D__s______Ss ss
2007-03-27 11:49:56 · answer #2 · answered by juno406 4 · 0⤊ 0⤋
It is a trait that is inherited from one parent. It is a trait that is predominantly carried by African Americans or those of Mediterranean descent.
Some hypothesize that the trait developed in an evolutionary response to malaria.
2007-03-27 10:56:14 · answer #3 · answered by BookAddict 3 · 0⤊ 0⤋
it results from a single amino acid substitution in the protein hemoglobin.
2016-02-21 14:11:11 · answer #4 · answered by Halmata 1 · 0⤊ 0⤋