Fluctuating dermatoglyphic asymmetry and the genetics of liability to schizophrenia.

Schizophrenic subjects were compared to normal and psychiatric control subjects for degree of fluctuating asymmetry in two dermatoglyphic traits, a-b ridge count and fingertip pattern. The schizophrenic group exhibited significantly greater fluctuating asymmetry than either control group. Furthermore, indicators of disease severity such as early onset and declining course of illness correlated with degree of asymmetry. Both of these observations are expected if a disorder has a polygenic basis, since fluctuating asymmetry is a marker of polygenic inheritance.