In every cell in the human body there is a nucleus, where genetic material is stored in genes. Genes carry the codes responsible for all of our inherited traits and are grouped along rod-like structures called chromosomes. Typically, the nucleus of each cell contains 23 pairs of chromosomes, half of which are inherited from each parent. Down syndrome occurs when an individual has a full or partial extra copy of chromosome 21.
Down syndrome is caused by a random error in cell division that results in the presence of an extra copy of 2.) chromosome 21. There are more than 50 features of Down syndrome. Down syndrome has all the same features or health problems. Down syndrome have 47 chromosomes. In rare cases, other chromosome problems cause Down syndrome. Having extra genetic material changes the way the brain and body develop.The extra part of the chromosome gets "stuck" to another chromosome and gets transmitted into other cells as the cells divide me times, a parent who does not have Down syndrome may carry a translocation in chromosome 21 that can be passed on to children and cause Down syndrome. There are no distinct cognitive or medical differences between people with translocation trisomy 21 and those with complete trisomy 21. Down syndrome is the most frequent chromosomal cause of mild to moderate intellectual disability, and it occurs in all ethnic and economic groups. In the United States, demographic factors also affect the risk for a child to be born with Down syndrome. These factors include geographic region, maternal education, marital status, and he symptoms of Down syndrome vary from person to person, and people with Down syndrome may have different problems at different times of their lives
- Upward slanting eyes, often with a skin fold that comes out from the upper eyelid and covers the inner corner of the eye .Down syndrome frequently show abnormalities in the blood cells which include the red cells (cells that carry oxygen throughout the body), white cells (infection-fighting cells) and platelets (cells that help to stop bleeding). Some of the changes found in the blood cells of individuals https://www.youtube.com/watch?v=uPy2WsHAls8with Down syndrome can be associated with other medical complications seen among . The most common blood cell abnormalities diagnosed in patients with Down syndrome include: polycythemia (also known as erythrocytosis), macrocytosis, thrombocytopenia, thrombocytosis, leucopenia, leukemoid reactions and transient myeloproliferative disorder.Individuals with Down syndrome have an increased risk for the development of precancerous conditions such as myelodysplastic syndrome, potentially cancerous conditions such as transient myeloproliferative disorder and cancerous conditions like leukemia.