Question

In South Africa, variegate porphyria is found in white South Africans at a higher frequency than would be expected if the population was in Hardy-Weinberg equilibrium. This population originated from a small group of Dutch settlers. The most likely explanation for the high frequency of variegate porphyria in this population is:

(A) selection for heterozygotes
(B) the founder effect
(C) immigration into the population
(D) selection against heterozygotes

Answer 1

The high frequency of variegate porphyria in white South Africans is most likely due to the founder effect, which occurred when a small group of Dutch settlers established the population, leading to the perpetuation of genetic traits present in the original colonists. The correct option is (B) the founder effect

Step-by-step explanation:

The most likely explanation for the high frequency of variegate porphyria in white South Africans, which originated from a small group of Dutch settlers, is the founder effect. This phenomenon occurs when a new population is established by a small number of individuals, and it results in the genetic structure of the new population being similar to that of the founders. The distinctive genetics of Afrikaners, with unusual incidences of genetic diseases like Huntington's disease and Fanconi anemia, is due to the founder effect, as evidenced in the case of the Dutch settlers in South Africa. In contrast, selection for heterozygotes, immigration, and selection against heterozygotes are other evolutionary forces that may affect allele frequencies, but in the context of variegate porphyria in South Africa, the founder effect is considered the primary cause of the observed high frequency of the disorder.

The correct option is (B) the founder effect