Loss of the N-myc oncogene in a patient with a small interstitial deletion of the short arm of chromosome 2.

To our knowledge, only four previous cases of distal chromosome 2p deletions exist in the literature. We present a patient with minor facial anomalies who had a distal interstitial deletion of the short arm of chromosome 2, del(2)(p24.2p25.1). This patient had many features seen in other patients with distal 2p deletion including short stature, "rectangular" facies, microcephaly, hypotonia, and mental retardation. This patient also has sensorineural hearing loss which has been described in one other patient with a similar deletion. The N-myc oncogene has been mapped to 2p24. By fluorescence in situ hybridization using a cDNA probe for the N-myc oncogene, this patient was found to have a deletion of the N-myc oncogene. This confirms the previous map location for N-myc.