The first Korean case of a newborn with 3p26 microdeletion and 5q35 microduplication inherited from paternal balanced translocation

ABSTRACT

Genetic imbalances are a major cause of congenital and developmental abnormalities. We report the first case of a 3p26 microdeletion and 5q35.2q35.3 microduplication in a newborn with multiple congenital anomalies evaluated using chromosomal microarray analysis (CMA) and fluorescence in situ hybridization (FISH). The patient was born at 30 weeks and 2 days of gestation with a body weight of 890 g. He had symmetric intrauterine growth restriction, microcephaly, facial dysmorphism (hypertelorism, blepharophimosis, mild low-set ears, high-arched palate, and micrognathia), and right thumb polydactyly. Echocardiography revealed an atrial septal defect and patent ductus arteriosus. Furthermore, CMA revealed a concurrent microdeletion in 3p26 and a microduplication in 5q35.2q35.3. FISH analysis showed that these genetic changes resulted from a translocation mutation between chromosomes 3 and 5. The patient’s mother had mild intellectual disability, short stature, and facial dysmorphism, while his father had a normal phenotype. However, parental FISH analysis revealed that the asymptomatic father carried a balanced translocation of chromosomes 3p26 and 5q35. CMA and FISH tests are useful for diagnosing neonates with multiple congenital abnormalities. Further parental genetic investigation and proper genetic counseling are necessary in cases of chromosomal abnormalities inherited from parental balanced translocations.