Down's syndrome, ageing and fragile sites.

Fragile sites have been interesting for mapping chromosomal regions involved in disease and ageing. The chromosomal fragile site expression from 38 Down's syndrome (DS) individuals aged 0-48 years was investigated in blood peripheral lymphocytes. Fragile sites were statistically characterized as the minimum expected number of lesions per band based on a Poisson distribution. The results showed that the fragile site 2q11 was associated with the DS condition and fragile sites 5q31, 6p21 and 9q12 with ageing in DS subjects. Fragility in 6p21 has also been associated with Alzheimer's disease patients.