Two patients from Turkey with a novel variant in the GM2A gene and review of the literature
-
Aslı İnci
,
Filiz Başak Cengiz Ergin
Abstract
Objectives
GM2 gangliosidosis is a rare form of inborn errors of metabolism including Tay-Sachs disease, Sandhoff disease, and GM2 activator deficiency. GM2 activator protein deficiency is an ultra-rare form of GM2 gangliosidosis. To date, 16 cases of GM2 activator protein deficiency have been reported in the literature, and among them, 11 cases were the infantile form of the disease. Here we report the first two patients from Turkey with the infantile form of the disease with a novel likely pathogenic variant.
Case presentation
A boy of eight months old presented to the metabolic department with very mild neurological deterioration, although he had achieved early developmental milestones at the appropriate time. The parents also had a daughter who had lost skills progressively before one year of age. The boy was evaluated and bilateral cherry-red spots were found with no abnormality in either metabolic screening including β-hexosaminidase or cranial magnetic resonance imaging. A novel homozygous likely pathogenic variant in GM2A was detected in a next-generation sequence panel revealing GM2 activator protein deficiency. His sister was investigated after he was diagnosed with GM2 activator deficiency and it was found that she had the same variant as her brother.
Conclusions
This case report emphasizes that in the event of normal β-hexosaminidase activity, GM2 activator protein deficiency could be underdiagnosed, and further molecular analysis should be performed. To the best of our knowledge, this boy is one of the youngest patient diagnosed with very mild symptoms. With this novel pathogenic variant, these patients have expanded the mutation spectrum of GM2 activator protein deficiency.
Author contributions: Aslı İnci, İlyas Okur, Fatih Ezgü followed up the patients. Gursel Biberoğlu performed the metabolic tests of the patient. Aslı İnci, Filiz Başak Cengiz Ergin, Fatih Ezgu performed the genetic analysis of the patient. Aslı İnci, Filiz Başak Cengiz Ergin drafted the manuscript. Leyla Tümer and Fatih Ezgü critically revised the manuscript and all the authors approved the final version of the manuscript.
Competing interests: None.
Ethical approval: The patient consent form was obtained from parents.
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© 2021 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
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- Original Articles
- Mental and somatic health in university students with type 1 diabetes: new results from DiaSHoT18, a cross sectional national health and well-being survey
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- What is the relationship between obesity and new circadian rhythm parameters in Turkish children and adolescents? A case-control study
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- Is overweight/obesity a risk factor for atopic allergic disease in prepubertal children? A case–control study
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- Serum sclerostin concentration is associated with specific adipose, muscle and bone tissue markers in lean adolescent females with increased physical activity
- Validation of a continuous measure of cardiometabolic risk among adolescents
- Clinical characteristics and molecular genetic analysis of a cohort with idiopathic congenital hypogonadism
- The genetics and clinical manifestations of patients with vitamin D dependent rickets type 1A
- Switching from conventional therapy to burosumab injection has the potential to prevent nephrocalcinosis in patients with X-linked hypophosphatemic rickets
- Case Reports
- Asymptomatic pituitary apoplexy induced by corticotropin-releasing hormone in a 14 year-old girl with Cushing’s disease
- Two patients from Turkey with a novel variant in the GM2A gene and review of the literature
- Familial hyperphosphatemic tumoral calcinosis in an unusual and usual sites and dramatic improvement with the treatment of acetazolamide, sevelamer and topical sodium thiosulfate
- Pediatric diabetic ketoacidosis presenting with Streptococcus intermedius brain abscess
Articles in the same Issue
- Frontmatter
- Review Article
- Provocative growth hormone testing in children: how did we get here and where do we go now?
- Original Articles
- Mental and somatic health in university students with type 1 diabetes: new results from DiaSHoT18, a cross sectional national health and well-being survey
- Prevalence of elevated liver enzymes and their association with type 2 diabetes risk factors in children
- What is the relationship between obesity and new circadian rhythm parameters in Turkish children and adolescents? A case-control study
- Body fat distribution in trunk and legs are associated with cardiometabolic risk clustering among Chinese adolescents aged 10–18 years old
- Is overweight/obesity a risk factor for atopic allergic disease in prepubertal children? A case–control study
- Importance of individualizing treatment decisions in girls with central precocious puberty when initiating treatment after age 7 years or continuing beyond a chronological age of 10 years or a bone age of 12 years
- Blood pressure dynamics after pubertal suppression with gonadotropin-releasing hormone analogs followed by estradiol treatment in transgender female adolescents: a pilot study
- Levels of physical activity and barriers to sport participation in young people with gender dysphoria
- Serum sclerostin concentration is associated with specific adipose, muscle and bone tissue markers in lean adolescent females with increased physical activity
- Validation of a continuous measure of cardiometabolic risk among adolescents
- Clinical characteristics and molecular genetic analysis of a cohort with idiopathic congenital hypogonadism
- The genetics and clinical manifestations of patients with vitamin D dependent rickets type 1A
- Switching from conventional therapy to burosumab injection has the potential to prevent nephrocalcinosis in patients with X-linked hypophosphatemic rickets
- Case Reports
- Asymptomatic pituitary apoplexy induced by corticotropin-releasing hormone in a 14 year-old girl with Cushing’s disease
- Two patients from Turkey with a novel variant in the GM2A gene and review of the literature
- Familial hyperphosphatemic tumoral calcinosis in an unusual and usual sites and dramatic improvement with the treatment of acetazolamide, sevelamer and topical sodium thiosulfate
- Pediatric diabetic ketoacidosis presenting with Streptococcus intermedius brain abscess
