Down syndrome

Down Syndrome

What is Down syndrome

Down syndrome is considered to be one of the most common genetic diseases that arise from changes in a number of autosomes. This disease was identified and studied by an English doctor named John Langdon Down in the year 1866. In all patients the disease has an extra chromosome. In fact, this pathology is very common, and every year the number of infants with this disorder has been increasing more and more. Children born with this disease can be identified by their physical appearances. Such children are rather flat face, but very thick lips, slanting eyes and a broad flat tongue, which is rather deep longitudinal groove. Nape of these children is flattened, sloping forehead, but the ears are significantly reduced in the vertical direction. Moreover, these chidren have also been noted to have joined earlobes. Patients have mild and infrequent hair growth. Muscular hypotonia is another clear sign of this genetic disease. In most of the cases, children suffering from the disease are also found with chest deformity (Bateson, 2000). Their belly becomes noticeably jutting, with shorter limb than that of their peers. No one is immune from this disease because children with this disease can be born even to those parents who are fierce advocates of healthy lifestyles.

Role of Genetics in Development

The basic unit of genetic instructions is the gene, segments of chromosomes (DNA molecules containing genetic information), which directs the growth and development of human beings. A human being has 46 chromosomes found in pairs resulting in 23 pairs of chromosomes. Each gene instructions are written in a code consisting of bases, which are: adenine (A), guanine (G), cytosine (C), thymine (T) that is combined in pairs and always of the form A - T and C - G. The sequence of these ...