Genetic Testing Vital in Consanguineous Marriages

Genetic Testing Vital in  Consanguineous MarriagesGenetic Testing Vital in  Consanguineous Marriages

Consanguineous or intra-family marriages pose risks to offsprings of such couples.

In clinical genetics, a consanguineous marriage is defined as a union between two individuals who are related as second cousins or closer. Such marriages double the risk of having babies with life threatening birth defects, and therefore it is vital for prospective couples who are blood relatives to perform genetic screening, also known as karyotype test, prior to marriage.

The high costs of genetic screening (anywhere from $90 to $750), the absence of insurance for the procedure and lack of public awareness about the importance of genetic counseling, have engendered congenital defects and disorders among children of such marriages, reports ISNA.

Genetic testing is gaining recognition for the many advantages it has to offer in the prevention, management and treatment of congenital diseases. Among the many uses, genetic tests most commonly present an opportunity for individuals to be informed about their genetic predisposition to disease, and for couples to be aware of the possible genetic characteristics of their unborn children. With the spread of education and awareness on birth defects, consanguineous couples want to know whether their children will be physically or mentally abnormal or how the risks of birth defects can be reduced.

Dr. Sirous Zeinali, genetic specialist, says karyotype testing is not mandatory for all couples. However, couples who are related are advised to take genetic tests when they decide to have children to prevent disabilities peculiar to marriages among close relatives.

Karyotyping is a costly procedure and may not be required if couples have no family history of congenital defects. “There is no karyotype test for the general public, and if any medical center makes such a claim, it is fraudulent,” he added.

Zeinali said a family history of recurrent miscarriage, infertility, stillbirths, genetic abnormalities as well as congenital defects such as Down or Turner syndrome and diseases like thalassaemia are indications for the need to undergo genetic counseling before marriage.

Couples who have a child with developmental disability or special needs and are thinking of having another offspring should visit a counselor to ensure that their second child is not born with birth defects or medical problems. They may be prescribed genetic tests to prevent risks to the unborn child.

Consanguinity is deeply rooted among one-fifth of the world population mostly residing in the Middle East, West Asia and North Africa, as well as among emigrants from these communities residing in North America, Europe and Australia.

The mounting public awareness on prevention of congenital and genetic disorders in offspring is driving an increasing number of couples contemplating marriage and children in highly consanguineous communities to seek counseling.

Preconception and premarital counseling on consanguinity should be part of the training of healthcare providers particularly in highly consanguineous populations.

It is estimated that one billion of the current global population live in communities with a preference for consanguineous marriage, where intra-familial unions collectively account for 20–50 % of all marriages.