Delecja czyli ubytek fragmentu DNA z chromosomu 16 powoduje upośledzenie umysłowe, opóźnienie rozwoju i inne wady wrodzone u dzieci — informują naukowcy z USA na łamach pisma Nature Genetics.
Physical retardation, such as the inability of an infant to sit, walk, and coo at the age of most of its peers, is often the first symptom of mental retardation, autism, cerebral palsy, Down’s syndrome, and other illnesses.
Evan Eichler and colleagues from the University of Washington in Seattle analyzed the genomic sequences of more than 21 mentally retarded and retarded children. In 42 children from this group, scientists observed a deletion, i.e. a loss of a fragment of DNA. Among nearly 15 healthy people (in the control group), a similar mutation was found only in 8 children.
In addition, the researchers found that children with a chromosome 16 deletion and additional abnormalities in the structure of the chromosomes had more severe developmental disorders than children without this characteristic mutation. (PAP)