A de novo 1.4‐Mb deletion at 21q22.11 in a boy with developmental delay. Issue 4 (23rd January 2014)

• Record Type: Journal Article
• Authors: Fukai, Ryoko; Hiraki, Yoko; Nishimura, Gen; Nakashima, Mitsuko; Tsurusaki, Yoshinori; Saitsu, Hirotomo; Matsumoto, Naomichi; Miyake, Noriko
• Is Part Of: American journal of medical genetics. Volume 164:Issue 4(2014.)
• Page Start: 1021
• Page End: 1028
• Publication Date: 2014-01-23
• Subjects: Medical genetics -- Periodicals; 616.14205
• DOI: 10.1002/ajmg.a.36377
• Languages: English
• ISSNs: 1552-4825

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="ajmga36377-sec-0001" sec-type="section"> <p>Monosomy 21 is a very rare chromosomal abnormality. At least 45 patients with partial deletion involving 21q11 have been reported. Here, we report a Japanese boy who presented with pre‐ and postnatal growth delays, psychomotor developmental delay, microcephaly, and iris coloboma. Cytogenetic analysis revealed a de novo 1.4‐Mb deletion at 21q22.11 containing 19 protein‐coding RefSeq genes. We compared the clinical phenotypes between the present patient and 16 previously reported patients with a deleted region associated with postnatal growth delay and psychomotor developmental delay. Interestingly, <italic>ITSN1</italic> was the only gene deleted or disrupted in all cases; this gene is known to be associated with intellectual disability. Microcephaly and brain structural abnormalities including polymicrogyria and agenesis/hypoplasia of the corpus callosum may also result from haploinsufficiency of <italic>ITSN1</italic>, highlighting its clinical significance for the neurological features of patients with monosomy 21. © 2014 Wiley Periodicals, Inc.</p> </sec> </abstract>