As mentioned in the case of men, in the context of genetic testing, the karyotype is checked, namely the woman’s chromosomes are identified and studied. Humans have 46 chromosomes, two of which are sex-related (male XY, female XX). Karyotype testing is performed on a blood sample at any point and, consequently, the genetics lab identifies the 46 chromosomes and studies whether they are normal, if any are missing, if there is a supernumerary one or if part of one has broken off and attached elsewhere (this is called migration).
Fragile X syndrome is considered the second most common reason for mental retardation in boys, after Down syndrome. The disease is inherited through a sex-linked trait (via the X chromosome). This test is recommended for women with premature menopause or low ovarian follicle reserves.
If the man has been found to be a carrier of a cystic fibrosis mutation, then this is a mandatory for the woman to be checked, because, if she is also a carrier, there is a 25% probability that the child will present cystic fibrosis. This is a very serious disease that can even be fatal and, therefore, relevant tests must be performed for the woman, if the man has been found to be carrying a mutation.
