[Satellite association patterns in postpartum women and in newborn infants]

Different features of the satellite associations between the acrocentric chromosomes of 100 postpartum mothers, between 14 and 43 years of age, and 100 neonates (51 males and 49 females) from Puriscal, Costa Rica, were compared (400 cells were examined, 2 from each individual). Several types of satellite associations showed higher frequencies in the mothers than in the neonates. The associations most frequently found in the two groups were those of two chromosomes, followed by those of three chromosomes. The D/G ratio was 1.43 in the children and 1.40 in the mothers. The number of associations per cell in the mothers was almost twice that of the children. The mean number of acrocentric chromosomes per association was 2.2 in the children and 2.35 in the mothers. No significant difference was found between observed and expected values of D and G chromosomes in the two groups. Thus, the probable factors responsible for the increase of satellite associations in the mothers similarly influenced the two types of acrocentric chromosomes.