Dental Admissions Test (DAT) 2025 – 400 Free Practice Questions to Pass the Exam

Question: 1 / 400

What biological concept is demonstrated by the Bombay phenotype in the ABO blood group system, where individuals inherit A and B alleles but have type O blood due to the inability to produce the H antigen affecting A and B antigens?

Epistasis

The Bombay phenotype is a rare blood type characterized by the absence of A, B, and H antigens in individuals who have inherited A and B alleles from their parents. This occurs due to a mutation in the H gene, which is responsible for producing the H antigen that is required for the functioning of the A and B antigens. This phenomenon is an example of epistasis, which is a type of gene interaction where the expression of one gene is dependent on the expression of another gene. In this case, the H gene is epistatic to the A and B genes, as its expression is necessary for the production of A and B antigens. Therefore, options B, C, and D are incorrect as they do not explain the specific gene interaction observed in the Bombay phenotype.

Get further explanation with Examzify DeepDiveBeta

Codominance

Incomplete Dominance

Electrophoresis

Next Question

Report this question

Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy