Testing as a shield against genetic diseases

There may be 400 types of genetic diseases prevalent in the UAE, according to the UAE Genetic Diseases Association (UAE GDA).

Genetic diseases, which are caused by abnormalities in the human DNA, are known to be the fourth leading cause of death in the UAE. The country is also ranked sixth among 193 nations in order of birth defect prevalence, most of which occur due to genetic causes.

The statistics may be disturbing but advances in science are now the key to combating this issue, top geneticists in the country say

Nearly 30 per cent of couples who undergo fertility treatment [in the UAE] undergo genetic testing,” said Dr Ali Hellani, laboratory director at Viafet, a full-range genetics laboratory in the UAE. “This is a huge jump, because about six years back, only about five per cent of couples would have opted to undergo genetic screening,” Dr Hellani said

However, despite this reassuring increase, he believes there is a need to increase awareness on this issue. “More awareness can be created about just how many genetic diseases can be avoided [in newborns] with the proper diagnostic treatments and techniques. These include diseases that are common in the UAE, such as thalassaemia, haemophilia, autism, mental retardation and muscular dystrophy,” he added.

One of the main reasons that contributes to the prevalence of inherited diseases is the high rate of consanguineous unions in many cultures.

Worldwide, for instance, the consanguineous marriages contribute to about 10 per cent of childbirths

Dr Human Fatemi, a specialist in reproductive medicine and medical director of the IVI Middle East Fertility Clinic in Abu Dhabi, said about 60 per cent of children in the UAE are born from parents who are first- or second-degree cousins to one another.

For couples who wish to take adequate precautions regarding the health of their child, and get a diagnosis on the possibility of a genetic disease being passed down or occurring, the first and perhaps easiest is opting for carrier testing. This procedure helps couples determine the risks for their child inheriting a genetic disease. According to Dr Hellani, nearly 850 prevalent genes can now be detected in the UAE to screen for 300 diseases

Dr Panayota Zarmakoupis, consultant for obstetrics, gynaecology, reproductive endocrinology and infertility at the Medcare Fertility Centre, added that there is room to offer carrier testing more widely.

IVF the answer

Regarding the timing of the test, it ought to be early on during the process of family planning.

“Couples could check early on if they share the same genetic mutation, and therefore, have a high risk of a child inheriting a genetic disease. In such cases, they could opt for in vitro fertilisation (IVF),” Dr Zarmakoupis explained.

Once a couple decides to undergo IVF, the fertilised embryos can be biopsied to check for genetic anomalies in a process known as pre-implantation genetic diagnosis.

“The biopsies check to see if the embryos have the mutation, or if they have any other abnormalities in their DNA. Through this, only unaffected or healthy embryos can be implanted to ensure that the child is free from the disease,” Dr Zarmakoupis said.

In addition, genetic tests can also help cure a child born with a genetic disease.

“For instance, a child with a blood disorder can be treated with a bone marrow transplant. Such a transplant is least likely to be rejected after HLA [human leucocyte antigen] type testing is used,” Dr Hellani explained.

The HLA type testing identifies certain proteins in the blood called antigens. These antigens are markers on the cell-surface which help the human body tell the difference between itself and others. If the body detects cells with a different HLA, its immune system attacks the foreign body as a means of protection. This also leads to the rejection of transplanted organs with a different HLA.

So an HLA type test is first performed on the affected child. Then, when a couple conceives through IVF, the fertilised embryos are checked to find healthy ones with the same HLA type

“This can take multiple IVF trials, but it can be the means to curing an affected child. In the process of doing so, it also helps couple ensure that their newborn will be healthy as well,”Dr Walid Sayed, medical director and consultant for obstetrics, gynaecology, reproductive endocrinology and infertility at HealthPlus Fertility Centre.

Couples can also choose to select their children’s genders during IVF, especially as certain genetic diseases that are particularly prevalent in the region are gender specific. These include haemophilia, muscular dystrophy, severe autism and mental retardation

source : gulfnews