Thiamine responsive megaloblastic anemia syndrome: A novel homozygous SLC19A2 gene mutation identified. (23rd February 2015)

• Record Type: Journal Article
• Authors: Mikstiene, Violeta; Songailiene, Jurgita; Byckova, Jekaterina; Rutkauskiene, Giedre; Jasinskiene, Edita; Verkauskiene, Rasa; Lesinskas, Eugenijus; Utkus, Algirdas
• Is Part Of: American journal of medical genetics. Volume 167:Number 7(2015:Jul.)
• Page Start: 1605
• Page End: 1609
• Publication Date: 2015-02-23
• Subjects: Medical genetics -- Periodicals; 616.14205
• DOI: 10.1002/ajmg.a.37015
• Languages: English
• ISSNs: 1552-4825

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="ajmga37015-sec-0001" sec-type="section"> <p>Thiamine responsive megaloblastic anemia syndrome (TRMAS) is a rare autosomal recessive disorder especially in countries where consanguinity is uncommon. Three main features are characteristic of the disease – megaloblastic anemia, early onset deafness, and non‐type I diabetes. TRMAS is a Mendelian disorder; a gene <italic>SLC19A2</italic> coding high affinity thiamine transporter mediating vitamin B1 uptake through cell membrane has been identified. We present the first patient with TRMAS in Lithuania – a 3‐year‐old boy born to a non‐consanguineous family with a novel homozygous <italic>SLC19A2</italic> gene mutation. The patient had insulin dependent diabetes (onset 11 months), respiratory illness (onset 11 months), bilateral profound hearing loss (onset at 7 months, verified at 20 months), refractory anemia (onset 2 years), and decreased vision acuity and photophobia (onset 2.5 years). The psychomotor abilities developed according to age. Phenotypic evaluation did not reveal any dysmorphic features. The clinical diagnosis of TRMAS was suspected and daily supplementation with thiamine 100 mg was started. The condition of the patient markedly improved several days after the initiation of treatment. The results of <italic>SLC19A2</italic> gene molecular testing confirmed the clinical diagnosis – novel homozygous c.[205G>T], p.[(Val69Phe)] mutation changing conserved amino acid residue or even interfering the mRNA splicing. Clinical heterogeneity, diverse dynamics, and wide spectrum of symptoms are aggravating factors in the diagnosis. The possibility of treatment demands early recognition of disorder to facilitate the improvement of the patient's condition. © 2015 Wiley Periodicals, Inc.</p> </sec> </abstract>