Tuesday, August 2, 2011

Recessive Allele

A recessive allele is an allele which is not expressed when paired with a different dominant allele of the same gene. A recessive allele is usually expressed only when both homologous chromosomes carry the recessive allele. Heterozygotes involving recessive are not distinguishable phenotypically from dominant homozygotes. By convention, recessive alleles are written in lowercase letters, while dominant alleles in uppercase letters.