Dermatoglyphic indices and minor physical anomalies in patients with schizophrenia and related disorders, their first-degree biological relatives, and non psychiatric controls.

Abnormalities in dermatoglyphic indices and minor physical anomalies (MPAs) are two permanent markers of fetal development that have been studied in schizophrenia. This study sought to: (1) compare select dermatoglyphic indices across patients, first-degree relatives, and non psychiatric controls; (2) assess for associations between dermatoglyphic indices and symptoms in patients and schizotypal features in relatives and controls; and (3) examine correlations between dermatoglyphics and MPAs. The two types of markers were assessed in 62 patients with schizophrenia and related disorders, 36 of their unaffected first-degree relatives, and 47 non psychiatric controls. Symptoms were measured in patients and schizotypy was assessed in relatives and controls. Analyses took into account potential demographic confounders and non independence between patients and relatives. No significant differences in dermatoglyphic indices (total finger ridge count; ridge count asymmetry; numbers of arches, loops, and whorls) were found across the three groups. Patients' and their own relatives' dermatoglyphic indices were moderately to strongly correlated (rho=0.33-0.66). Dermatoglyphic indices were unrelated to patients' cross-sectional symptom severity and were generally unrelated to relatives' and controls' levels of schizotypy. Several correlations among dermatoglyphic indices and MPAs were found in this exploratory analysis, particularly among relatives and controls. Implications for future research are discussed.