Clinical and radiologic evaluation of a Turkish family with hypochondroplasia and a rare FGFR3 variant

Sadiye Ekinci; Yasemin Ülger; Mustafa Oğuz Acar; Ayşegül Ceran; Zehra Aycan; Ömer Suat Fitoz; Hatice Ilgın Ruhi

doi:10.1515/jpem-2021-0773

Article

Clinical and radiologic evaluation of a Turkish family with hypochondroplasia and a rare FGFR3 variant

Sadiye Ekinci , Yasemin Ülger , Mustafa Oğuz Acar , Ayşegül Ceran , Zehra Aycan , Ömer Suat Fitoz and Hatice Ilgın Ruhi

Published/Copyright: April 20, 2022

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From the journal Journal of Pediatric Endocrinology and Metabolism Volume 35 Issue 8

Abstract

Objectives

Hypochondroplasia (HCH) is characterized by disproportionate short stature and regarded as a milder form of achondroplasia (ACH), which is another skeletal dysplasia, both caused by variants in fibroblast growth factor receptor 3 (FGFR3) gene. HCH diagnosis is based on the clinical features and skeletal survey findings. The most common FGFR3 variant in HCH affects the codon 540, leading to substitution of asparagine with lysine in about 70% of patients.

Case presentation

Herein, we described the clinical and radiographical manifestations of HCH in affected members of a Turkish family with very rare Asn540Thr (c.1619A>C) variant within hot spot of the gene for this condition.

Conclusions

This is a very rarely reported variant in the literature and this report is the first case with this variant in Turkish population. The report also presents the phenotypic variability within a family with the same variant, which is inherent to HCH.

Keywords: FGFR3 ; hypochondroplasia; phenotypic variability

Corresponding author: Sadiye Ekinci, MD, Medical Genetics Department, Ankara University School of Medicine, Morfology Building, Ahmet Adnan Saygun Street, No:35, 06230 Altındağ, Ankara, Turkey, E-mail: ekincisadiye@gmail.com

Acknowledgments

We thank the family members who participated in this case study.

Research funding: None declared.
Author contribution: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
Competing interests: Authors state no conflict of interest.
Informed consent: Informed consent was obtained from all individuals included in this study.
Ethical approval: Ethics Committee approval is not required for this case report.

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Supplementary Material

The online version of this article offers supplementary material (https://doi.org/10.1515/jpem-2021-0773).

Received: 2021-12-27

Revised: 2022-03-07

Accepted: 2022-03-28

Published Online: 2022-04-20

Published in Print: 2022-08-26

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Supplementary Material

Articles in the same Issue

https://doi.org/10.1515/jpem-2021-0773

Keywords for this article

FGFR3; hypochondroplasia; phenotypic variability