By Elizabeth Paul
B.App.Sci., (App.Biology) R.M.I.T.,
Cert. Animal Technology, F.I.T.
Reprinted by permission of Elizabeth Paul and the Australian Alpaca Association (AAA)
The author wishes to thank Dr David Propert, formerly Associate Professor of Human genetics, Department of Applied Biology and Biotechnology, R.M.I.T., for his constructive comments and advice.
Introduction
Coat colour in mammals is almost entirely dependent on the presence or absence of the pigment, melanin, in the skin and hair. There are two distinct forms of this pigment: eumelanin (brown/black) and phaeomelanin (red/yellow).
Melanin is produced in granules by cells called melanocytes, which are concentrated in the hair follicles, the skin epidermis and the retina of the eye. Colour in these areas is determined by the size and shape, as well as by the type, number and distribution of the granules. The nature of the granules is affected by many factors, both internal and external. Colour inheritance patterns for small laboratory animals, particularly mice, and some larger domestic animals such as dogs, cats, horses and cattle have been intensively studied. Many of their genotypes and phenotypes have been described (Searle, A.G., 1968). Read more.