Down syndrome is a genetic disorder in which there is an extra full or partial chromosome For most people with Down syndrome, this anomaly causes a host of distinctive physical characteristics as well as potential health and medical problems. A person with this type of Down syndrome may have all the features of full trisomy 21, a few of them, or none at all. Many characteristics of full trisomy 21 are quite noticeable—a round face and upturned eyes, and a short, stocky build, for example. People with Down syndrome sometimes move awkwardly, usually due to low muscle tone hypotonia at birth that can interfere with physical development.
Craniofacial Anomalies pp Cite as. Persons with Down Syndrome DS have, in addition to intellectual deficits, specific dysmorphic facial features. These include small, simply formed ears with overlapping helices, upward slant of palpebral fissures, epicanthal folds, small nose with depressed nasal bridge, mid-face hypoplasia, and a small oral cavity with broadened alveolar ridges and narrow palate Pueschel, Such distinguishing physical characteristics, it is believed, make the person with Down Syndrome appear markedly different from others, even physically unattractive to some. There is concern Olbrisch, lest the characteristic facial features of persons with DS impede their social integration. Unable to display preview. Download preview PDF. Skip to main content. Advertisement Hide.
There are 23 pairs of chromosomes, for a total of Half the chromosomes come from the egg the mother and half come from the sperm the father. This XY chromosome pair includes the X chromosome from the egg and the Y chromosome from the sperm. In Down syndrome, there is an additional copy of chromosome 21, resulting in three copies instead of the normal two copies. Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome This extra genetic material causes the developmental changes and physical features of Down syndrome. Down syndrome varies in severity among individuals, causing lifelong intellectual disability and developmental delays. It's the most common genetic chromosomal disorder and cause of learning disabilities in children. It also commonly causes other medical abnormalities, including heart and gastrointestinal disorders.
This causes physical and mental developmental delays and disabilities. Many of the disabilities are lifelong, and they can also shorten life expectancy. However, people with Down syndrome can live healthy and fulfilling lives. Recent medical advances, as well as cultural and institutional support for people with Down syndrome and their families, provides many opportunities to help overcome the challenges of this condition. In all cases of reproduction, both parents pass their genes on to their children. These genes are carried in chromosomes. Half of the chromosomes are from the mother, and half are from the father. The baby ends up with three copies, or an extra partial copy, of chromosome 21, instead of two. This extra chromosome causes problems as the brain and physical features develop. This is the most common form of Down syndrome.