INTERSTITIAL DELETION 2Q33.3-Q34 IN A BOY WITH A PHENOTYPE RESEMBLINGTHE SECKEL-SYNDROME

A boy presented at 5 weeks with a syndrome of pre-and postnatal growth retardation, microcephaly, muscular hypotonia, and facial anomalies r esembling those seen in Seckel syndrome or microcephalic primordial dw arfism I. Analysis of prometaphase chromosomes, fluorescent in situ hy bridization (FISH), and molecular studies showed the presence of a de novo chromosome 2 deletion that could be defined as del(2)(q33.3q34)pa t, Parental chromosomes were normal, except for the presence of a pate rnal supernumerary marker identified by FISH as der(15).On follow-up o f the patient during the next months length development appeared norma l and the diagnosis of Seckel syndrome was withdrawn, Clinical finding s of previously published cases with interstitial deletion of at least 2q33.3-q34, the deletion present in the propositus, are reviewed and include pre-and postnatal growth retardation, psychomotor retardation, microcephaly, micrognathia, and abnormal/low-set ears; findings also present in the propositus. These findings resemble those described in the Seckel syndrome, Noteworthy is the finding that 2/3 of the 60 revi ewed cases originally reported as having Seckel syndrome apparently be long to a heterogeneous group of low birth weight microcephalic dwarfi sm I yet to be clearly defined, In these patients no chromosome 2q del etion has been reported so far. Retrospective analysis could show if a subgroup of these patients carry submicroscopic deletions at 2q33.3-q 34. Alternatively, molecular analysis of this region may be warranted in newly diagnosed patients with Seckel syndrome-like manifestations, (C) 1997 Wiley-Liss, Inc.