Mitochondrial Haplotype Frequencies in Oysters: Neutral Alternatives to Selection Models

Abstract

The animal mitochondrial genome is a small circular molecule of about 15--42kb (kilobase pairs). Although present in multiple copies in each cell, it is essentially haploid and its inheritance is predominantly maternal. The molecule undergoes very rapid evolution at the DNA sequence level, due in part to the apparent lack of repair during replication. Because of its simple mode of inheritance, its ease of extraction and analysis and the extensive variation that can be observed in most animal populations, mitochondrial DNA (mtDNA) has been the focus of many population surveys since the late 1970s.1,2