Detection of 22q11.2 deletion among 139 patients with Di George/Velocardiofacial syndrome features

Abstract

Cytogenetic and FISH analysis was performed in 139 patients to detect the pathognomonic of Di George/ Velocardiofacial syndrome (DGS/VFCS) deletion 22q11.2. An abnormal karyotype was revealed in 2/139 cases (47, XXY and 46, XX, 2p+). A deletion was found in 17/139 (12.2%) patients (14 males/ 3 females), inherited in 3 (2 maternal and 1 paternal). Patients with 22q11.2 deletion exhibited facial dysmorphic features (82%), congenital heart defects (70%), immunological problems (47%), multiple congenital anomalies (64%), hypocalcemia (47%), mental retardation/learning difficulties (35%), cleft palate/velopharyngeal insufficiency (23.5%), seizures/hypotonia (23%) and growth retardation (12%). Among 56/139 patients with detailed available clinical data, the 22q11.2 deletion was confirmed in all cases with hypocalcemia and in over half of the cases with multiple congenital anomalies, immunological problems and hypotonia/seizures (70%, 60% and 57%, respectively). Genetic reevaluation of 39 patients without the 22q11.2 deletion contributed to the classification of 14 (37%) under different syndromes, emphasizing the need for stricter referral criteria.