Yes, the Spanish Fertility Society (SEF) recommends that all gamete banks perform a basic genetic screening of their donors. Due to their prevalence, penetrance and severity, this basic genetic screening in Spain should include cystic fibrosis, spinal muscular atrophy, non-syndromic sensorineural deafness and the most prevalent hemoglobinopathies (such as thalassemia and sickle cell anemia). And in oocyte donors, in addition, the study related to fragile X syndrome.
Thus, donors presenting pathogenic variants for these diseases included in the basic genetic screening can only be used when the existence of pathogenic variants in the recipient is ruled out (by means of genetic matching) and in the case of Fragile X syndrome, they will be discarded according to the risk of transmitting this syndrome.
In addition, each gamete bank will be able to perform an extended genetic screening study of carriers that allows the study of more than 300 hereditary genetic diseases. This study includes serious prevalent diseases and rare diseases that appear in one out of every 100,000 births.
When egg or sperm donation is used, since the donors have undergone genetic testing, the same test would be performed on the woman (in the case of sperm donation) or on the man (in the case of egg donation to his partner) if the patients so decide. In this way, the ideal donor can be selected and the risk of having an affected child can be reduced. If the result is not suitable, the donor will be changed to minimize the risk of having a sick child.
It is important to note that, although the risk is minimized after testing, it is never completely eliminated as "de novo" mutations may appear or a genetic disease not included in the test may appear.
