Dermatoglyphics and abnormal palmar flexion creases as markers of early prenatal stress in children with idiopathic intellectual disability

A number of studies have shown the importance of dermatoglyphics as markers of prenatal disturbance in developmental disorders of unknown origin. Gene tic and non-genetic factors are involved in the aetiology of intellectual d isability (ID), although the cause remains unknown in up to 50% of cases. T he aim of the present study was to analyse dermatoglyphic traits and abnorm al palmar flexion creases as markers of environmental prenatal stress in ch ildren with idiopathic ID (IID) using a case-control study design. Three de rmatoglyphic variables, which have been reported as altered in other congen ital disorders, were considered were studied in a sample of 62 children wit h HD (IQ < 70) and 75 healthy controls (IQ > 70): (1) fingerprint patterns; (2) total a-b ridge count (TABRC) and (3) abnormal palmar flexion creases (APFCs). More arches, the simplest fingerprint pattern, and more radial loo ps, an unusual pattern, were found in IID cases in comparison to controls ( chi (2)(3) = 9.26; P=0.02), with especially marked differences in boys (chi (2)(3) = 6.5; P = 0.0008). A significant increase of APFCs was also found in the affected children (chi (2)(4) = 28.52; P <0.00; odds ration = 3.86, 95% confidence interval = 1.77-8.47). For TABRC, the differences between II D cases and controls failed to reach the conventional level of significance . These findings suggest that environmental factors acting early in develop ment, or mechanisms involving an interaction of genotype and environment co uld be involved in the aetiology of some cases of ID.