Down's syndrome. A seven year old boy with Down's syndrome (trisomy 21) playing with his mother. Down's syndrome results from a chromosomal abnormalit

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Down's syndrome. A seven year old boy with Down's syndrome (trisomy 21) playing with his mother. Down's syndrome results from a chromosomal abnormality; each body cell contains an extra chromosome (number 21) so that there are 47 chromosomes rather than the usual 46. This results in a variable mental handicap; IQ usually lies between 30 and 80 (almost all affected children have learning potential), and distinctive appearance with upward-sloping eyes. Heart defects, congenital deafness and leukaemia are more common in people with Down's syndrome. About one in 650 babies shows this abnormality and this rate increases with increased maternal age.

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Size: 3543px × 2726px
Photo credit: © HATTIE YOUNG/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 21, child, condition, disability, disease, disorder, downs, handicapped, healthcare, medical, medicine, playing, syndrome, trisomy