The origin of genetic mapping lies in the discoveries by Mendel that the inheritance of phenotypic traits could be predicted. The original characteristics in pea that Mendel followed all segregated independently

1Department of Biology, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106-7080. ae-mail: [email protected] be-mail: [email protected] *Corresponding author List of abbreviations after the text.