ß 2007 Wiley-Liss, Inc. American Journal of Medical Genetics Part A 143A:1354–1357 (2007) Clinical Report Interstitial Deletion of 6q Without Phenotypic Effect Kerstin Hansson, 1 * Karoly Szuhai, 2 Jeroen Knijnenburg, 2 Arie van Haeringen, 1 and Joke de Pater 1,3 1 Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands 2 Department Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands 3 Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands Received 13 November 2006; Accepted 23 February 2007 Cytogenetically detectable euchromatic deletions without phenotypic consequences are rarely encountered. We report on a 34-year-old woman with normal intelligence referred for karyotyping because of recurrent abortions. With the exception of a bicuspid aortic valve without hemodynamic consequences, which is a common minor anomaly in the general population, no dysmorphic features were found on physical examination. Conventional chromosome analysis (GTG-banding) revealed an interstitial deletion in the long arm of chromosome 6. With array comparative genomic hybridization (array-CGH) the size of the deletion was estimated to be between 9.9 and 11.6 Mb and the refined karyotype was 46,XX,del(6)(q22.31q23.1). ß 2007 Wiley-Liss, Inc. Key words: interstitial deletion without phenotypic effect; deletion 6q; array comparative genomic hybridization How to cite this article: Hansson K, Szuhai K, Knijnenburg J, van Haeringen A, de Pater J. 2007. Interstitial deletion of 6q without phenotypic effect. Am J Med Genet Part A 143A:1354 –1357. INTRODUCTION Cytogenetically visible deletions of euchromatic material are mostly accompanied by mental retarda- tion and various physical abnormalities. However, a few reports have been published showing that euchromatic deletions can be compatible with a normal phenotype: deletion of band 2p12 [Lambert and Collinson, 1991; Barber et al., 2005], 2q14.1 [Sumption and Barber, 2001; Barber et al., 2006], 3p26 [Knight et al., 1995], 5p14 [Overhauser et al., 1986; Hand et al., 2000; Johnson et al., 2000; Zhang et al., 2005], 6q24.1 [Kumar et al., 1999], 8p23.2 and 23.3 [Reddy, 1999], 8q24.21 [Batanian et al., 2001], 9p21.3 [Pelly and Barnes, 1992], 11p12 [Barber et al., 1991], 11q14.3 [Li et al., 2002], 13q21 [Couturier et al., 1985], and 16q21 [Witt et al., 1988; Callen et al., 1993; Hand et al., 2000]. Patients with an interstitial deletion in the long arm of chromosome 6 are usually mentally retarded and have, depending on the size and location of the deletion, various physical abnormalities [Hopkin et al., 1997], with the excep- tion of one case mentioned above [Kumar et al., 1999]. To the best of our knowledge this is the first report of a phenotypically normal woman with an interstitial deletion of region 6q22.31q23.1. CLINICAL REPORT A 34-year-old woman with normal intelligence was referred for chromosomal analysis because of recur- rent abortions. With the exception of a bicuspid aortic valve without hemodynamic consequences, which is a common minor anomaly in the general population, no dysmorphic features were found on physical examination. Her growth was normal as well. She has had two spontaneous abortions, one healthy daugh- ter and a son with mild dysmorphic features, developmental delay, and behavioral problems. CYTOGENETIC ANALYSIS AND ARRAY-CGH Chromosome analysis was performed on PHA stimulated lymphocytes from peripheral blood cultures using GTG-banding at a resolution level of 550 bands. Fluorescence in situ hybridization (FISH) *Correspondence to: Dr. K. B. M. Hansson, LDGA, Clinical Cyto- genetics, Leiden University Medical Center, Postbus 9600, Postzone S-06- P, 2300 RC Leiden, The Netherlands. E-mail: K.B.M.Hansson@LUMC.nl DOI 10.1002/ajmg.a.31783