One in 500 male babies is born with a second X chromosome, a condition known as Klinefelter syndrome. The vast majority of these boys develop language-related learning disabilities and dyslexia.
By
Willow Lawson, published on March 01, 2003 - last reviewed on February 13, 2007
Danny's struggles with learning to read may not be laziness or a
lack of intelligence. Instead, an extra chromosome could be to
blame.
One in 500 male babies is born with a second X chromosome—in
addition to the normal XY—a condition known as XXY, or Klinefelter
syndrome. The vast majority of these boys, about 80 percent, develop
language-related learning disabilities and dyslexia. Speech delay,
extreme shyness and small genitalia are often clues that a boy has XXY.
Many also have delayed motor skills.
Early diagnosis and therapy, especially during a child's first five
years, can drastically reduce the effects of the disorder, according to a
study co-authored by Carole Samango-Sprouse,
Ed.D. She shows that with therapy, XXY boys learn
to walk six months before boys without therapy.
The obstacle to therapy is often diagnosis. Some 75 percent of XXY
boys never get help because they go through life not knowing they are
different, according to Samango-Sprouse.
"They usually look very normal, although they are often tall and
very attractive kids," she says. She notes that XXY boys may not be
hampered intellectually when therapy is given.
Generally, there are few obvious signs of the disorder. Only one in
three of these boys will develop enlarged breasts—once considered a
hallmark of the condition. Later in life, they tend to have sparse facial
and body hair and a rounded body type. And they are more likely to be
overweight if not identified and treated. Many XXY males, who rarely
produce enough sperm to father children, are diagnosed when they seek
treatment for infertility.
"Pediatricians should be on the lookout for these kids," says
Samango-Sprouse. "If a young child has a learning disability or other
symptoms, a chromosomal analysis should be ordered." Other chromosome
disorders, such as XXX and XYY—which also cause learning difficulties in
children, including girls, can be detected this way.
Tags:
body hair,
chromosomal analysis,
chromosome,
chromosome disorders,
disability,
education,
enlarged breasts,
extra chromosome,
extreme shyness,
first five years,
genitalia,
lack of intelligence,
language,
laziness,
learning,
learning difficulties,
learning disabilities,
male babies,
pediatricians,
speech delay,
x chromosome,
xxy boys,
xxy males,
xyy
