A novel synonymous homozygous variant [c.2538G>A (p.Thr846Thr)] in TRPM6 in a patient with hypomagnesemia with secondary hypocalcemia
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Sezer Acar
,
Karl Peter Schlingmann
Abstract
Objectives
Hypomagnesemia 1, intestinal (HOMG1) is characterized by neurological symptoms that occur due to hypocalcemia and hypomagnesemia and caused by mutations in the TRPM6. Most of the identified variants in TRPM6 lead to premature termination: nonsense, frameshift, deletion, and splice site mutations.
Case presentation
Herein, we report a 1.5 month-old case who presented with convulsion due to hypocalcemia and hypomagnesemia in the early infancy. Sequencing of TRPM6 revealed a novel homozygous synonymous variant [c.2538G > A (p.Thr846Thr)] in the last codon of exon 19, which is most likely to affect the splicing. We report a novel homozygous synonymous variant in the TRPM6 leading to HOMG1, expanding the mutational spectrum.
Conclusions
Synonymous mutations that were previously considered as harmless should be evaluated at the nucleotide level, keeping in mind that they may affect splicing and cause to the disease.
Acknowledgments
We gratefully thank our patient and her family for their consent.
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Research funding: None declared.
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Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Competing interests: Authors state no conflict of interest.
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Informed consent: Informed consent was obtained from all individuals included in this study.
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Ethical approval: The local Institutional Review Board deemed the study exempt from review.
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© 2021 Walter de Gruyter GmbH, Berlin/Boston
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Articles in the same Issue
- Frontmatter
- Review Article
- An endocrine perspective on menstrual suppression for adolescents: achieving good suppression while optimizing bone health
- Original Articles
- Anthropometric, metabolic, and reproductive outcomes of patients with central precocious puberty treated with leuprorelin acetate 3-month depot (11.25 mg)
- Evaluation of the resilience of the girls with central precocious puberty treated with gonadotropin-releasing hormone analog
- The effect of GnRH stimulation on AMH regulation in central precocious puberty and isolated premature thelarche
- Association of the apoptotic marker APO1/Fas with children’s predisposing factors for metabolic syndrome and with mean platelet volume
- Serum adiponectin, body adiposity and metabolic parameters in obese Egyptian children with Down syndrome
- Urinary iodine and thyroglobulin are useful markers in infants suspected of congenital hypothyroidism based on newborn screening
- Comparison of plasmapheresis with medical apheresis in terms of efficacy and cost in the acute treatment of hypertriglyceridemia in children with lipoprotein lipase deficiency
- Clinical, biochemical and genotypical characteristics in biotinidase deficiency
- High uric acid levels in overweight and obese children and their relationship with cardiometabolic risk factors: what is missing in this puzzle?
- Optimizing pediatric histrelin implantation to improve success rates in clinic without sedation
- Determinants of ultra-processed food consumption in Brazilian children and adolescents with type 1 diabetes mellitus: a cross-sectional study
- The prevalence, immune profile, and clinical characteristics of children with celiac disease and type 1 diabetes mellitus in the state of Qatar
- Case Reports
- A rare and preventable aetiology of neurodevelopmental delay and epilepsy: familial glucocorticoid deficiency
- Giant plurihormonal pituitary adenoma in a child – case study
- The usefulness of copeptin for the diagnosis of nephrogenic diabetes insipidus in infancy: a case report
- A novel synonymous homozygous variant [c.2538G>A (p.Thr846Thr)] in TRPM6 in a patient with hypomagnesemia with secondary hypocalcemia
- Idiopathic juvenile osteoporosis in a child: a four-year follow-up with review of literature
