Dermatoglyphics--a possible biomarker in the neurodevelopmental model for the origin of mental disorders.

INTRODUCTION: Dermatoglyphic pattern formation and differentiation are complex processes which have been in the focus of research interest ever since dermatoglyphics became a science. The patterns' early differentiation and genetic uniqueness as well as the relatively simple methods used to obtain and store fingerprints make it possible to study the relationship between certain dermatoglyphic characteristics and the underlying pathological processes in a number of diseases, including mental disorders. AIM: The present review reports published data from fundamental and clinical studies on dermatoglyphics primarily in schizophrenia and bipolar disorder to lend additional support for the neurodevelopmental hypothesis in the etiology of these disorders. Following an analysis of the theories of dermatoglyphics formation and the complex association between ridge patterns and central nervous system in early embryogenesis, an attempt is made to present dermatoglyphics as possible biological markers of impaired neurodevelopment. CONCLUSIONS: The contradictory data in the literature on dermatoglyphics in mental disorders suggest the need for further studies on these biological markers in order to identify their place in the neurodevelopmental etiological model of these diseases.

Biomarker profile of minor physical anomalies in schizophrenia patients.

AIM: The aim of this study was to determine the frequency and topographical distribution of minor physical anomalies (MPAs) in schizophrenia patients and control subjects, and the ability of the items of the Waldrop scale to predict the patient-control status. MATERIAL AND METHODS: 128 schizophrenic patients (66 men, 62 women) and 103 normal controls (49 men, 54 women) were evaluated for MPAs with a modified version of the Waldrop scale. RESULTS: Compared with controls, schizophrenia patients showed a higher incidence of almost all studied MPAs, differences being statistically significant for 12 items: fine electric hair, abnormal hair whorls, epicanthus, adherent ear-lobes, lower edges of the ears extending backward/upward, malformed ears, asymmetrical ears, high/arched palate, furrowed tongue, smooth/rough spots on the tongue, III toe > or = II toe, big gap between I and II toe. Some anomalies occurred with almost equal frequency in schizophrenic patients and controls, while others were more than 10 times more common in patients (odds ratio: 0.62 - 10.55). The distribution frequency of MPAs in schizophrenia tended to increase in the cranial direction. Nine predictor MPA biomarkers successfully distinguished 81.10% of patients, 81.55% of controls, and 81.30% of all examined subjects. CONCLUSIONS: The elevated incidence of MPA biomarkers in schizophrenia patients implies impaired neurodevelopment that increases the risk for the development of schizophrenia. The pattern of changes in the morphological characteristics suggests they may be a random outcome of a general neurodevelopmental defect or may reflect different neurodevelopmental defects that allow better characterization of schizophrenia patients subgroups.