Question

When two genetic loci produce identical phenotypes in cis and trans position, they are

• A. Pseudoalleles
• B. Multiple alleles
• C. Part of same gene
• D. Different genes

Answer 1

The correct option is A Pseudoalleles

The cis-trans complementation test is done to determine if two mutations are allelic or nonallelic by constructing a heterozygote. Pseudoalleles are the genes that functionally behave as allelic pairs but structurally they are different genes present on two different genetic loci, not allelic pairs. Therefore, they behave as alleles in cis-trans test and produce identical phenotypes. Multiple alleles refer to the presence of more than two alleles of a gene which occupy the same genetic locus. The parts of the same gene occupy the same genetic locus and different genes occupy different genetic loci but do not produce an identical phenotype in cis-trans test. Thus, the correct answer is option A.