Maternal age and dermatoglyphic asymmetry in man: another look.

The effect of maternal age on the degree of bilateral asymmetry found in digital ridge counts was explored as a possible explanation for a previously detected maternal effect, where significantly less variation was observed in thumb ridge counts between the two sibships within families of female monozygotic (MZ) twins than between sibships within families of male MZ twins. Contrary to a previous report which found a tendency for ridge count asymmetry to increase with maternal age, this study could show no such relationship. It was concluded that while the exact nature of the maternal effect noted for thumb ridge counts is unclear, it is little influenced by maternal age.