The Mendelian heredity
var _gaq _gaq = The simple inheritance. Complicating matters are in fact the presence of many genes, in fact the vast majority of the most common phenotypes in humans arises from the interaction of multiple genes in humans are indeed a few characters controlled by a single gene that in many cases are also responsible for the life of debilitating disorders such as Huntington
syndrome and cystic fibrosis Friday, September 10, 2010
Church Anniversary Progam
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It becomes clear how the genetic investigation in humans is complex and full of obstacles. We have said that most of the characters that are inherited in humans follow a Mendelian type, this is mainly due to the fact that human beings do not plan some of them on a purely genetic choices, the time between one generation and the other is very long, many diseases occur in middle age, the families for many children may have are relatively small when compared with the countless children who pttiene dal'incrocio of a plant such as those that Mendel used, it follows that in statistical genetic analysis is complex, there are no clean lines it controlled unions. Geneticists overcome these limitations by studying a large number of families or different generations of a large family to obtain models that can explain the inheritance of characters. A family history can be represented by a tree, perhaps more correct to say that a pedigree chart summarizes the order in which the most important genetic characteristics of a family.
How to interpret a family tree?
quadtrati I represent males, circles females, the diamonds indicate that sex is not specified, the members of a family with a character is marked by a square or a circle depending on whether full are male or female. A horizontal line joining a boy or a girl means a union, double line indicates that the union took place between consenguinei, that is a union between relatives. A horizontal line over a series of symbols indicates the children of the parents themselves are typically aligned from left to right according to the Odin-born Roman numerals on the left or right indicate the generations. In the picture next
(Clicking it enlarges more) lists the various characteristics of a pedigree. 
observing the simple rules we can recognize the characters by analyzing a dominant or recessive pedigree.
Dominant characters.
Dominant characters.
1)
2)
The characters show a dominant pattern of inheritance vertical, that is, the character appears in every generation 
3) both parents show a character could not have children affected if both parents are etrozigoti. recessive traits.
1) Individuals who
All progeny Affected individuals must show character.
3)
rare recessive traits may show a pattern of inheritance called horizontal before the character appears between different individuals in each generation, but is not visible in the early generations.
rare recessive traits may show a pattern of inheritance called horizontal before the character appears between different individuals in each generation, but is not visible in the early generations.
4)
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