Abstract: The purpose of this paper is to analyze the fluctuating asymmetry ( FA) of dermatoglyphic a-b ridge counts in individuals with schizophrenia from Ningxia, China. Fluctuating asymmetry refers to small random deviations from perfect symmetry in bilaterally paired structures. It is the result from interactions between developmental disturbance and developmental stability, and it has a low heritability. Fluctuating asymmetry can be as a measure of individual quality and also an indicator of developmental stability. Computing FA was done using the absolute differences between bilateral measurements ( calculated as FA = | R - L | ) . Inked dermatoglyphic samples were collected from individuals who gave their informed consent, and the required parameters for this research were analyzed. A random sample was taken from 134 people with schizophrenia ( 70 male and 64 female)and compared with 331 healthy controls ( 170 male and 161 female) . The results were that Individuals with schizophrenia had a reduced mean a-b ridge counts compared to the control group( P < 0.01); There was a significant difference between groups in FA of a-b ridge counts ( t= 2.668, P< 0.01) with individuals with schizophrenia having a significantly higher fluctuating asymmetry of a-b ridge counts; In a distribution of a-b ridge count, schizophrenia was significant different in the group of FA ≥10.It may indicate that people with schizophrenia had a higher developmental instability in their earlier fetation. These results may indicate that during the course of fetal development, the schizophrenia fetus is much more sensitized to a variety of external environments.

Key words: Schizophrenia; Dermatoglyphic; a-b ridge count; Fluctuating asymmetry; Developmental stability