Clinical and Genetic Study of 1p36 Deletion Syndrome in Three Tunisian Patients

Purpose: 1p36 deletion syndrome is a clinically recognizable syndrome characterized by typical dysmorphic features such as straight eyebrows, deep-set eyes, midface hypoplasia, orofacial clefting, pointed chin and low-set ears. It is also associated with developmental delay, microcephaly, hypotonia and growth retardation. Cardiac malformations, hearing loss and ophthalmologic anomalies are also described. To date, many cases have been reported worldwide. However, this syndrome had never been reported in Tunisian population. We describe in this study the clinical and molecular characteristics of three Tunisian patients with the 1p36 deletion syndrome.

Patients and methods: The clinical characteristics of the three patients were reviewed. Karoytypes, array CGH and FISH were performed for genetic diagnosis.

Results: All patients had brachymicrocephaly, development delay and growth retardation. Two of them had typical dysmorphic features consisting of straight eyebrows, midface hypoplasia, pointed chin and low-set ears. The other patient had orofacial clefting. Karyotypes were normal in all cases. Array CGH showed 1p36 monosomy in all patients. Besides, it revealed 22q13 trisomy in one patient whose father had a translocation t (1;22). These findings were validated by FISH.

Conclusion: The 1p36 deletion syndrome is a common malformation syndrome that is not always clinically recognizable. Array CGH was a significant tool for patients in whom the diagnosis was not suspected.