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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.

Genetic studies have demonstrated that nonsyndromic cleft is composed of two separate entities: the cleft palate only and cleft of the lip, alveolus with or without cleft palate; both have a heterogeneous genetic background and environmental factors contribute to the onset of these malformations. The role of transforming growth factor alpha (TGF-A) was considered possible, but conflicting results have been reported. To detect if TGF-A is involved in the onset of cleft diseases, a series of patients with nonsyndromic clefts and control subjects were analyzed with regard to protein expression. Forty-three patients with nonsyndromic clefts and 21 unaffected subjects were enrolled in this study. Paraffin-embedded specimens were matched with TGF-A antibody and then scanned with a computerized image analyzer. TGF-A was scored as absent, moderately (from 10% to 30%), and highly expressed in epithelium, gland, and muscle. Data were statistically analyzed with a Kruskal-Wallis test. Comparison between control subjects and patients with clefts showed that only gland and epithelium reached a significant P value. A subsequent comparison between cleft of the lip, alveolus with or without cleft palate and cleft palate only groups demonstrated a statistically significant difference only for gland. TGF-A was decreasingly expressed in unaffected, cleft of the lip, alveolus with or without cleft palate, and patient with cleft palate only and thus further strength has been given to its role in the onset of the disease. © 2007 Muntaz B. Habal, MD.

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.