[Array comparative genomic hybridization detection of a de novo 4q21.21-q22.1 deletion in a child with severe growth retardation].

OBJECTIVE: To analyze a child with developmental delay, severe mental retardation, speech delay and muscular hypotonia.

METHODS: The karotypes of the child and her parents were analyzed with G-banding analysis. Their genome DNA was also analyzed with array comparative genomic hybridization (array-CGH).

RESULTS: No karyotypic abnormality was detected at cytogenetic level. However, array-CGH has identified a de novo 4q21.21-q22.1 deletion in the child, which has a size of 12.1 Mb.

CONCLUSION: The de novo interstitial 4q21.21-q22.1 deletion probably underlies the main clinical manifestation in the child. Array-CGH is useful for diagnosing children with multiple congenital anomalies with unclear etiology.