How it is caused and other information
how is down syndrome inherited/caused
some symptoms may be
- Down syndrome causes a distinct facial appearance
- intellectual disability
- developmental delays
- may be associated with thyroid or heart disease
no cure found.
.2. Dr. Jerome Lejeune discovered Down syndrome is a genetic disorder whereby a person has three copies of chromosome 21 instead of two.
There are also very rare forms of Down syndrome (less than 6%) called Translocation Down Syndrome or Mosaic Down Syndrome in which not all of the chromosome is triplicated or not all cells of the body carry the extra chromosome.
3. Down syndrome is the most frequently occurring chromosomal disorder and the leading cause of intellectual and developmental delay in the U.S. and in the world.