Gonosomal dominant inheritance

Gonosomal dominant inheritance (GD) is the transmission of a trait of interest, the allele of which is located on a gonosome. The mutated allele has a complete dominance relationship with the original allele. The vast majority of gonosomally linked traits have gene located on the X chromosome; an exception could be the pseudoautosomal region on the Y chromosome. In the case of GD inheritance, both males (hemizygotes), and females, who are most often heterozygous, will be affected. The typical feature of the pedigree of a fully penetrant, X-linked dominant disease involves affected males. Because they pass the Y chromosome on to their sons, we find 100% affected daughters and no affected sons in their offspring - see the picture below (of course, there is a theoretical possibility of acquiring the mutated allele from the mother if both parents have the same disease).

The following picture is an example of a family tree with the occurrence of gonosomal dominant inheritance.

Examples

 * X-linked hypophosphatemic rickets (vitamin D resistant rickets), OMIM307800
 * Incontinentia pigmenti, OMIM308300

Related links

 * Autosomal dominant inheritance
 * Autosomal recessive inheritance
 * Gonosomal recessive inheritance
 * Non-Mendelian inheritance