Journal of Heredity 2004:95(1)
© 2004 The American Genetic Association 95:76-80
Brief Communication |
Inheritance of White Head Spotting in Natural Populations of South American Water Rat (Nectomys squamipes Rodentia: Sigmodontinae)
From the Institute of Cytology and Genetics, Russian Academy of Science, Novosibirsk 630090, Russia (Axenovich, Zorkoltseva, and Borodin), Novosibirsk University, Novosibirsk, Russia (Axenovich, Zorkoltseva, and Borodin), Institute of Tropical Medicine of Oswaldo Cruz Institute, Rio de Janeiro, Brazil (D'Andrea), National Museum of the Federal University of Rio de Janeiro, Rio de Janeiro, Brazil (Fernandes), and Division of Genetics, National Institute of Cancer, Rio de Janeiro, Brazil (Bonvicino). We thank Claudia Horta de Almeida for taking care of the captive breeding population of Nectomys squamipes, Juliano Chagas Silva and Stella Franco for help in checking spots in the skins of specimens from the National Museum, and Dr. João Alves for granting access to the mammal collection of the National Museum of Rio de Janeiro. We also thank Rodrigo Mexas for helping with the photographs. This work was supported by research grants from the Brazilian National Research Council (CNPq)/PRONEX Foundation for Promoting Research of the State of Rio de Janeiro (FAPERJ), Oswaldo Cruz Foundation (IOC/PAPES/FIOCRUZ), Russian Foundation for Basic Researches (RFBR), and Federal Program "Russian Universities" (UNIROS).
Address correspondence to P. M. Borodin, Institute of Cytology and Genetics, Novosibirsk 630090, Russia, or e-mail: borodin{at}bionet.nsc.ru.
Specimens with white head spots are present at low frequency in the natural populations of South American water rat (Nectomys squamipes) and absent in the sibling species Nectomys rattus. We analyzed the pattern of inheritance of the phenotype using complex segregation analysis of pedigrees of a captive-bred population of N. squamipes. We found that the inheritance of the white head spot in this species can be described within the framework of the major gene recessive model with incomplete penetrance of genotypes.