| description | Protein which, if defective, causes Down's syndrome, a condition due to the presence of three copies of chromosome 21 (trisomy 21), characterized by some degree of intellectual disability, short stature and poor muscle tone. Common (1 in 700 live births); incidence increases with maternal age. The cause is usually non-disjunction at meiosis but occasionally a translocation of fused chromosomes 21 and 14 |
