Genetic and Clinical Approach To Microcephaly: A 5-Year Single Center Experience

Abstract

Microcephaly is a dysmorphic feature characterized by small head size more than two standard deviations below the mean for age, sex, and ethnicity. There are several etiological factors ranging from environmental toxins or infections to genetic disorders. We report clinical, radiological, and molecular genetic investigations of patients with microcephaly from a single center over 5-year period. There were 92 patients with a genetic diagnosis. Based on their genetic diagnosis, we grouped patients into three categories: (1) microcephaly with copy number variations (CNVs), (2) microcephaly with single gene disorders, and (3) microcephaly with aneuploidies. The most common category was aneuploidy in 59% of the patients, followed by single gene disorders in 23% of the patients and CNVs in 18% of the patients. We think that history and physical examination guide physicians to choose the most appropriate genetic testing to identify underlying diagnosis.

Keywords

chromosomal microarray analysis - copy number variants - microcephaly - whole exome sequencing

Publication History

Received: 29 June 2020

Accepted: 14 October 2020

Article published online:
19 November 2020

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