Interstitial deletion of bands 11q21 -> 22.3 in a three-year-old girl defined using fluorescence in situ hybridization on metaphase chromosomes

A 3-year-old girl has a de novo deletion of 11q21-22.3. The patient was stu died because of minor anomalies, disproportionate short stature, and develo pmental delay, The deletion was first detected by conventional cytogenetic analysis and defined further by using chromosome 11-specific YAC clones by fluorescent in situ hybridization (FISH) on metaphase chromosomes. Three YA C clones, 11H7, 4A5, and IH4, were lacking from one of the patient's chromo some 11. Trigonocepahly, hypertelorism, apparently low-set ears, mild renal abnormality, and delay in speech development found in our patient are simi lar findings in other published interstitial deletion cases, Our study show s that a molecular cytogenetic approach is useful in defining the specific location and the extent of an interstitial deletion in cytogenetically diff icult areas such as 11q. (C) 1999 Wiley-Liss, Inc.