Case Report
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Med Genet. Mar 10, 2023; 11(1): 1-7
Published online Mar 10, 2023. doi: 10.5496/wjmg.v11.i1.1
Phenotypic and cytogenetic features of an Iranian child with tetrasomy 18p syndrome: A case report
Sara Esmaeili, Cory J Xian
Sara Esmaeili, Cory J Xian, UniSA Clinical and Health Sciences, University of South Australia, Adelaide 5001, SA, Australia
Author contributions: Esmaeili S and Xian CJ designed the research study; Esmaeili S performed the research; Esmaeili S and Xian CJ analyzed the data and wrote the manuscript; all authors have read and approved the final manuscript.
Informed consent statement: Written informed consents have been obtained from the parents of the patient for the genetic test and for publishing this paper. The study was conducted in accordance with the Declaration of Helsinki. It was approved by the Ethics Board of Solale Laboratory in Tehran, Iran and it was carried out as part of the medical genetic diagnosis of the disorder of the patient in Solale Laboratory.
Conflict-of-interest statement: The authors declare no conflict of interest.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Cory J Xian, PhD, Professor, UniSA Clinical and Health Sciences, University of South Australia, North Terrace, GPO Box 2471, Adelaide 5001, SA, Australia. cory.xian@unisa.edu.au
Received: November 30, 2022
Peer-review started: November 30, 2022
First decision: January 12, 2023
Revised: January 16, 2023
Accepted: March 1, 2023
Article in press: March 1, 2023
Published online: March 10, 2023
Processing time: 99 Days and 21.7 Hours
Abstract
BACKGROUND

Tetrasomy 18p is a rare chromosome abnormality disorder known to have considerable variability in clinical features and gathering data from different cases will help clinicians and researchers learn about its genotype-phenotype relationship and diagnosis.

CASE SUMMARY

Herein, we have reviewed the literature on phenotypic features of this disorder and described the phenotypic and cytogenetic features of a girl of early childhood with tetrasomy 18p for the first time from Iran. This patient showed a strong sense of smell (a unique feature not reported previously for this syndrome), had clenched hand, pes planus, forward head posture in walking and hirsutism (dysmorphic features less reported), and showed 10 clinical features that are generally observed in previously reported cases, including developmental delay/intellectual disability, triangular face, smooth philtrum, feeding difficulties, hypotonia, epicanthus, strabismus, history of constipation, growth retardation and foot anomalies. G-banding chromosome analysis from peripheral blood revealed an abnormal female karyotype with a small marker chromosome (47,XX, +mar), and oligo-array comparative genomic hybridization displayed a gain of 14Mb of the 18p arm containing 56 Online Mendelian Inheritance in Man (OMIM) genes in this patient. Overall, this patient seems to have mild phenotypes.

CONCLUSION

This Iranian tetrasomy 18p child displays a uniquely strong sense of smell, some less reported dysmorphic features and ten features generally reported.

Keywords: Tetrasomy 18p; Phenotypic features; Clinical features; Chromosome abnormality; Cytogenetic analysis; Case report

Core Tip: Gathering data from different cases for the rare tetrasomy 18p chromosome abnormality disorder will facilitate mastering its genotype-phenotype relationship and diagnosis. This report described features for the first time for an Iranian patient. Compared to previously reported cases, this Iranian child displays a uniquely strong sense of smell, some less reported dysmorphic features and ten features generally reported. Her cytogenetic analyses revealed a small marker chromosome with a gain of 14Mb at the 18p arm. Apart from the usual clinical assessments, the non-invasive prenatal genetic testing is suggested to be used as a more accurate screening for detecting tetrasomy 18p.