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Mendelian genetics of humans exophenotype deals only with properties in the domain of qualitative variations and /or that quantitative properties that can be described in arbitrary categories, such as it were Mendel’s variety of low and high pea stalks. Therefore, this area classical genetics coverages of only those properties that behave according to the model monogenic inheritance, i.e. simple gene inheritance. According to the model Mendelian inheritance, if a child, at least from one of the parents gets dominant allele will have dominant phenotypic variant of observed properties. Only those who get a recessive allele from both parents exhibit the recessive phenotypes. Those who gets dominant allele from one parent and recessive than the other, will be the dominant variant features. Among the infinitely large number of potentially describable feature, very few that can be introduced in a purely Mendelian traits, because most of the phenotypic expression of the exophenotypic traits is the showpiece incomplete dominance, codominance and quantitative contributions from smaller or larger number of genes (see: Polygenic inheritance, Oligogenic inheritance).〔Dobzhansky T. (1970): Mankind evolving: The evolution of the human species. Bantam Books, New York, ISBN 05526-539-0X; ISBN 978-05526-5390-9.〕〔Hadžiselimović R. (2005): Bioanthropology - Biodiversity of recent man. Institute for Genetic Engineering and Biotechnology (INGEB), Sarajevo, ISBN 9958-9344-2-6. (in Bosnian).〕 Theoretically, the recessive phenotype can skip any number of generations, remaining "dormant" in heterozygous "carriers", until they have children with someone who has one or both recessive alleles, which will transfer to his/her child. If second partnet is recessive homozygote, the chance for expression of recessive phenotype is 50%, and if, as mentioned holder, and he heterozygote, in their offspring will appear 25% of individuals with recessive phenotype. The studies of the morphological - anatomical, undoubtedly inherited properties, faces particular difficulties because of incomplete gene expressiveness or penetrance which control them, regardless of their affiliation to any of the described models of inheritance. Most of those traits that exhibit a high heritability degree was listed in hardcover McKusick's Mendelian Inheritance in Man until the 10's editions. Many of them are still included in today's OMIM's edition.〔OMIM-http://www.omim.org/〕 Before the discovery of DNA identification, many of these features are worldwide used as the genetic markers in medicolegal practice, including the cases of disputed paternity. ==Human traits with probable or uncertain simple inheritance patterns== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Mendelian genetics of humans exophenotype」の詳細全文を読む スポンサード リンク
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