Xiao Li married young man a fat guy, happy for the whole family, relatives and friends came to congratulate was crowded! But good times do not last long, just over the Moon, and banquet, children suddenly bleed more than, overnight to the hospital, ultimately failed to save a child\'s life.
Xiao Li in tears, she really can not bear this heavy blow. Doctors told them that children die of hemophilia. This is a bleeding of genetic diseases, is the mother inherited sex-linked recessive, passed by the female, male cases. Inspection, Xiao Li is the carriers of the hemophilia gene. As carriers, pathogenesis of Xiao Li I will not, make the occurrence of her male offspring, female offspring and becomes the new gene carriers, also affecting their male descendants. Doctors warn Xiao Li, only girls in the future, not a boy, or tragic will happen.
Hemophilia and against men, seems to never \"abuse\" if female. What is this thing? It turns out that many recessive genes in the human x chromosome controlling genetic disease, hemophilia is one of a kind. Female x chromosomes even with pathogenesis gene does not only become the carriers of hemophilia. This is because females have two x chromosomes, needed two recessive genes on the x chromosome at the same time with only cases. But the two are coudao x chromosome with a recessive disease genes with very little opportunity, frequency of onset is about one-ten thousandth. Males have only one x chromosome, as long as a gene will be ill occurrence frequency of about one-one hundredth. Therefore, clinically, most seen in patients with hemophilia are males. This is called x-linked recessive hereditary disease, disease genes by genetic mother.
Young couples, if in your family has such patients with genetic diseases, please you must seriously do genetic counseling and prenatal checks, fetal sex determination under the medical supervision, control and avoid the birth of children with, so as not to regret at that time.
