Original ArticlesRecurrent 1q21.1 deletion syndrome: report on variable expression, nonpenetrance and review of literatureUpadhyai, Priyankaa; Amiri, Eram Fatimaa; Guleria, Vishal Singha; Bielas, Stephanie L.b; Girisha, Katta Mohana; Shukla, AnjuaAuthor Information aDepartment of Medical Genetics, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, Karnataka, India bDepartment of Human Genetics, University of Michigan, Ann Arbor, Michigan, USA Received 1 August 2019 Accepted 27 April 2020 Correspondence to Anju Shukla, MD, DM, Department of Medical Genetics, Kasturba Medical College, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India, Tel: +918202922726; fax: +918202571927; e-mail: [email protected] Clinical Dysmorphology: July 2020 - Volume 29 - Issue 3 - p 127-131 doi: 10.1097/MCD.0000000000000327 Buy Metrics Abstract The clinical phenotype of 1q21.1 microdeletion syndrome is highly heterogeneous. It is characterized by dysmorphic facial features, microcephaly, and developmental delay. Several congenital defects, including cardiac, ocular, skeletal anomalies, and psychiatric or behavioural abnormalities, have also been described. Here, we report on two siblings with substantial intrafamilial phenotypic variability carrying a heterozygous deletion of the 1q21.1 region spanning a known critical genomic area (~1.35 Mb). The microdeletion was inherited from the unaffected father. Patients described here show a spectrum of clinical features, a portion of which overlap with those previously reported in patients with 1q21.1 microdeletions. In addition, we review the clinical reports of 66 individuals with this condition. These findings extend and substantiate the current clinical understanding of recurrent copy number variations in the 1q21.1 region. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.