Distribution of a Human RFLP in the ACTG2 (ACTA3) Gene Among African-American and Caucasian populations

Abstract. Restriction fragment length polymorphisms (RFLPs) are variations in DNA sequences that can be detected by digestion with restriction enzymes. RFLPs are used to study variation and evolution within populations. This study focused on a specific PvFLP occurring within the human ACTG2 (formerly ACTA3) gene. ACTG2 encodes a γ-actin specifically expressed in mammalian enteric muscle. The RFLP occurs within the first intron and, while not a linkage marker for any genetic condition, has implications as a marker in human evolution. Humans normally have two copies of each chromosome. Each chromosome contributes one allele towards the pair examined using Mendelian genetics. An earlier study of the RFLP, conducted among Japanese and Caucasian populations, published the finding that the RFLP allele occurred twenty-one times more frequently in Caucasian populations. This study expanded analysis on this RFLP by surveying allelic frequencies in African Americans. Two hypotheses to explain earlier allelic result...