Clinical findings in cases with 9q deletion encompassing the 9q21.11q21.32 region

We report on a case with developmental delay and dysmorphic craniofacialfeatures, and a novel~15.2 Mb interstitial deletion within 9q21.11q21.32confirmed with array comparative genomic hybridization (aCGH). A twentytwo month old boy with inability to walk without support, absent speech,and attention deficit and hyperactivity disorder was seen in our clinic. Hiscraniofacial examination revealed relative macrocephaly, facial asymmetry,frontal bossing, sparse medial eyebrows, hypertelorism, broad base to nose,smooth philtrum, large mouth, operated cleft lip and wide spaced teeth. Thehigh resolution binding (HRB) chromosome analysis revealed an interstitialdeletion 46,XY,del(9)(q21) confirmed by aCGH revealing; 46,XY,der(9)(pter→q21.11::q21.32→qter).arr9q21.11q21.32(71,069,763-86,333,272)X1dn.Genotype-phenotype correlations of sixteen cases with 9q21 deletion havingdifferent breakpoints and variable length revealed common characteristicfeatures including severe developmental delay, epilepsy, neuro-behaviouraldisorders and facial dysmorphism including hypertelorism, smooth philtrumand thin upper lip. The smallest overlapping deleted region in all definedcases to date including our case comprised four genes. Among these deletedgenes as in our case, especially RORB is considered to be a strong candidatefor neurological phenotype.

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