Copy number variations on chromosome 2: impact on human phenotype, a cross-sectional study

Beatriz Sousa; Ana Grangeia; Joel Pinto; Helena Santos; Sofia Dória

doi:10.1097/j.pbj.0000000000000198

Copy number variations on chromosome 2: impact on human phenotype, a cross-sectional study

Porto Biomed J. 2023 Feb 7;8(1):e198. doi: 10.1097/j.pbj.0000000000000198. eCollection 2023 Jan-Feb.

Authors

Beatriz Sousa¹, Ana Grangeia^{1

2

3}, Joel Pinto^{1

3}, Helena Santos⁴, Sofia Dória^{1

3}

Affiliations

¹ Department of Pathology, Genetics Service, Faculty of Medicine, University of Porto, Portugal.
² Medical Genetics Service, Centro Hospitalar Universitário de São João, Porto, Portugal.
³ I3S-Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal.
⁴ Child and Adolescent Neuroscience Unit, Centro Hospitalar Vila Nova de Gaia/Espinho-CHVNG, Vila Nova de Gaia, Portugal.

Abstract

Background: Copy number variations (CNVs) on chromosome 2 are associated with a variety of human diseases particularly neurodevelopmental disorders. Array comparative genomic hybridization (aCGH) constitutes an added value for the diagnosis of neurodevelopmental or neuropsychiatric diseases. This study aims to establish a genotype-phenotype correlation, reporting CNVs on the chromosome 2, contributing for a better characterization of the molecular significance of rare CNVs in this chromosome.

Methods: To accomplish this, a cross-sectional study was performed using genetic information included in a database of the Department of Genetics of the Faculty of Medicine and clinical data from Hospital database. CNVs were classified as pathogenic, benign, variants of unknown significance, and likely pathogenic or likely benign, in accordance with the ACMG Standards and Guidelines.

Results: A total of 2897 patients were studied using aCGH, 32 with CNVs on chromosome 2, 24 classified as likely pathogenic, and 8 as pathogenic. Genomic intervals with a higher incidence were one 2p25.3 and 2q13 regions.

Conclusions: This study will help to establish new genotype-phenotype correlations, allowing update of databases and literature and the improvement of diagnosis and genetic counseling which could be an added value for prenatal genetic counseling.

Keywords: 2p12p11.2 deletion syndrome region; array comparative genomic hybridization; chromosome 2; copy number variations; neurodevelopmental disorders.