Non-syndromic orofacial clefts in Southern Italy: pattern analysis according to gender, history of maternal smoking, folic acid intake and familial diabetes

Summary Background Genetic studies have demonstrated that non-syndromic clefts of the lip, alveolus and palate have an heterogeneous genetic background, and that environmental factors contribute to the onset of this malformation. Therefore studies on different and homogeneous populations can be useful in detecting potentially related environmental and genetic factors. Purpose The aim of the present study was to evaluate whether gender, folic acid intake, family history of diabetes and/or smoking during pregnancy were associated with a specific type of cleft in a group of patients affected by non-syndromic clefts, collected from Southern Italy. Material and methods Data from one hundred and twenty-six patients were evaluated retrospectively. Each cleft was described as composed by separate antomical entities such as lip, alveolus, primary and secondary palate. None had an isolated alveolar cleft and this was used as internal control. Pattern analysis was used to detect differences in the frequencies of any possible combination of 7 types of clefting stratified according to the studied variables. Data were analysed by comparing observed proportions. Results Isolated cleft palate as well as right-sided clefts of lip, alveolus and palate were more frequent in females ( p = 0.0014 and 0.0281, respectively), while left sided clefts were more frequent in males ( p = 0.0359 ) . A lack of consumption of folic acid was associated with an higher incidence of clefts of the left lip ( p = 0.018 ) , while familial diabetes was associated more often with isolated cleft palate ( p = 0.0014 ) . Conclusions Gender-related results were comparable with those found in Northern Italy and other countries. Environmentally related results disclosed specific subclasses of clefting associated with lack of folic acid consumption and familial diabetes.