Down’s syndrome, one of the most common genetic disorders in children, occurs when there are three instead of the two usual copies of the chromosome 21 due to an error in the process of cell division. As a result of this ‘trisomy’, people with the syndrome have extra copies of more than 300 genes. The syndrome is associated with intellectual disabilities, a delay in cognitive ability and physical growth, distinctive facial features like flat face, slanted eyes, short necks, etc., and sometimes heart problems and other health effects. Researchers have discovered that the extra chromosome inherited in the syndrome impairs learning and memory because it leads to low levels of SNX27 protein in the brain. Children born with genetic birth defects like Down’s syndrome are at an increased risk of developing childhood cancer, says a study.
Down’s syndrome is usually identified at birth. The nuchal translucency scan or the NT scan conducted between the 11 and 13 weeks of pregnancy can help assess the foetal risk of developing the syndrome. Amniocentesis and chorionic Villus Sampling coupled with the results of an NT scan gives an accurate estimation. A simple non-invasive blood test called non-invasive analysis for chromosomal examination (NACE) which has a near-zero risk to foetus and has no risk of abortion can now detect the syndrome in a pregnant female within three months of pregnancy.
Down’s syndrome remains an incurable condition. But, acceptance by the family and early intervention can go a long way in ensuring that a child with the syndrome is able to live a normal life and be socially independent. Potential cure has emerged with the identification of a compound that appears to reverse the learning deficits associated with the syndrome.