The first part of this article. Medical genetic inheritence can be divided into four types. Autosomal recessive and Dominant types and dominant and recessive x-linked. The types of autosomal, recessive both dominant have been discussed in previous articles. Let's now talk about the type of gender-related or rather bound inheritence x.
X-linked recessive inheritance
1. There are "oblique" transmission, i.e., in the pedigree, the line drawn by the affected persons is oblique.
2. Only males are affected, females are only carriers.
3. For the progeny of a female carrier has 50% probability of affected son and 50% probability of daughters being carriers.
4. For the descendants of an affected male, none of the threads will carry line, while all daughters will be carriers.
A female can manifest a character bound to x if the normal x chromosome is inactivated life fetal (Lyonization) or if it is the offspring of a male of female, and are affected carrier, or if the unaffected x-chromosome is structurally abnormal as in Turner's syndrome. Example: Hemophilia disease of Christmas, pseudo-hypertrophic muscular dystrophy.
X-linked dominant inheritance
1. The number of affected women is doubling the number of affected males.
2. The affected male going of chromosome y sons (and not the X chromosome), accordingly, all affected male sounds are normal, while all girls affected male are abnormal.
3 Affected females passes the x-chromosome mutant half of his daughters and sons and consequently, half half girls and half threads are affected.
Disease is usually milder females, due to gene on the other X chromosome, for example, type of vitamin D resistant rickets hypo-phosphatemic
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