There are over 250 recognized sex-linked diseases, affecting every organ system.
Of these, 95% affect males, (Emery, 1968). Despite these many sex-linked diseases, at
present prenatal diagnosis can specifically be made in fewer than 40 diseases. (Emery,
1968). These sex-linked diseases are individual rare and some are named after
physicians who described them, for example, Hemophilia A and B, Duchenne muscular
dystrophy, fragile-X syndrome, Fabry disease, Hunter syndrome, Lesch-Nyhan syndrome,
and Menkes steely-hair syndrome. The following discourse considers the reasons for the
importance of prenatal diagnosis, heredity disorders, and disfiguring birth
defects.(Nora,1989).
Fabry disease is a biochemical disorder caused by a missing enzyme. (Mulinsky,
1989). A complex fatty substance accumulates in the body because of the missing
enzyme which would ordinarily break this compound into pieces.(Nora,1989). This
missing enzyme causes kidney and blood-vessel problems that lead to high blood
pressure, kidney failure and strokes.(Mulinsky, 1989). After many years of symptoms,
most patients have died in their thirties and forties owing to a lack specific treatment.
English: Genetics cause of mental retardation. fro...
English: Dermatophagia - extreme nail biting / bit...
English: Cherry red spot as seen in Tay Sachs dise...A biochemical disorder also caused by a missing enzyme is the Lesch-Nyhan
syndrome, an extremely unpleasant disorder characterized not only by profound mental
retardation and features of brain damage (stiff limbs with peculiar movements), but also
self-mutilation, (Jones, 1988). Given good care and attention however, these patients
may live on many years in their profoundly retarded state. They often require restraining,
tying their hands, to prevent them from mutilating themselves.
Another Affected children with Menkes steely-hair syndrome have hair that feels
similar to steel wool; in addition, they are retarded. The basic defect in this condition
concerns the way the body handles copper.
Only a few of these sex-linked disorders can now be diagnosed in the fetus,
(Stein, 1994). At the present time, the only recourse parents have in the case of sex-...