triple X syndrome Tuesday 26 February 2008 Definition: Triple X
syndrome, also called trisomy X or 47,XXX, is characterized by
the presence of one extra X chromosome in each of a female’s
cells. This condition occurs in about 1 in 1,000 newborn girls.
Five to 10 girls with triple X syndrome are born in the United
States each day. Most often, this chromosomal change causes no
unusual physical features or medical problems. Females with
triple X syndrome are sometimes taller than average and have an
increased risk of learning disabilities and delayed speech and
language skills. Developmental delays and behavioral problems
are also possible, but these characteristics vary widely among
affected girls and women. Most females with triple X syndrome
have normal sexual development and are able to conceive
children.