A diagnosis of discernment: Identifying a novel ATRX mutation in myelodysplastic syndrome with acquired α-thalassemia

New heritable ATRX mutation identified by whole exome sequencing and review

Background

The mutations in the ATRX gene have been shown to cause two types of disorders: inherited mutations lead to alpha thalassemia X-linked mental retardation (ATR-X) syndrome and acquired somatic mutations cause alpha thalassemia myelodysplastic syndrome (ATMDS). Here we report a case of ATRX gene mutation without completely features of ATR-X or ATMDS syndromes. Moreover we review previous reports of ATRX gene mutations in both ATR-X syndrome and ATMDS.

Methods

After sample collection and DNA extraction, whole exome sequencing was performed using Illumina HiSeq PE150 apparatus. The results were confirmed using Sanger sequencing for the patients and his relatives. Literature review was performed based on the published data in Web of science, Science direct, Springer link and Pubmed databases.

Results

We identified a hemizygous missense ATRX gene mutation (ATRX, c.2388A > C, p. K796N) as a new disease-causing variant in the patient, heterozygous situation for his mother and his father was hemizygous for wild type allele. The literatures of patients were reviewed regarding the ATR-X syndrome.

Conclusions

According to previous findings, inherited ATRX mutations are associated with a broad spectrum of clinical presentations. Therefore a person with a mild α-thalassemia phenotype may also has mutation in ATRX gene. Accordingly, it is critical for geneticist and physicians to increase awareness in molecular diagnosis of α-thalassemia patients.

A novel ATRX splice variant causing acquired HbH disease in myelodysplastic syndrome with excess blasts-1

A 60-year-old male with myelodysplastic syndrome with excess blasts-1 had unexplained microcytic hypochromic anemia. The cause of his anemia was revealed on supravital staining, hemoglobin studies and next-generation sequencing to be a novel hemizygous potentially pathogenic missense/splice site variant NM_000489.5:c.6848A>C, (p.Lys2283Thr) in exon 31 of the ATRX gene.