Iron Refractory Iron Deficiency Anemia Due to 374 Base Pairs Deletion in the TMPRSS6 Gene

The role of TMPRSS6 gene polymorphism in iron resistance iron deficiency anaemia (IRIDA): a systematic review

Iron resistance iron deficiency anaemia is a rare autosomal recessive disorder characterized by hypochromic microcytic anaemia, low transferrin saturation and inappropriately high hepcidin levels. The aetiology of this condition is rooted in genetic variations within the transmembrane serine protease 6 (TMPRSS6) genes, responsible for encoding matriptase-2, a pivotal negative regulator of hepcidin. We conducted a systematic search across four electronic databases, yielding 538 articles in total out of which 25 were finally included and were preceded further, aiming to prognosticate prevalent single nucleotide polymorphisms (SNPs) and detrimental genetic alterations. This review aims to elucidate the effects of various SNPs and pathogenic mutations on both haematological and biochemical parameters, as well as their potential interethnic correlation. Employing bioinformatics tools, we subjected over 100 SNPs to scrutiny, discerning their potential functional ramifications. We found rs1373272804, rs1430692214 and rs855791 variants to be most frequent and were having a significant impact on haematological and biochemical profile. We found that individuals of European ancestry were more prone to have these variants compared to other ethnic groups. In conclusion, this review not only sheds light on the association of TMPRSS6 polymorphism in iron resistance iron deficiency anaemia (IRIDA), but also highlights the critical need for further investigations involving larger sample size and more diverse ethnic groups around the globe. These future studies will be vital for gaining a stronger and more reliable understanding of how these genetic differences are linked to the development of IRIDA.

Response to Prolonged Duration of Therapeutic Dose Oral Iron Therapy in a Girl With Novel TMPRSS6 Gene Variants: A Case Report and Review Literature

Iron-refractory iron deficiency anemia (IRIDA) is an autosomal recessive disorder caused by mutations in the TMPRSS6 gene, which impair iron homeostasis. We reported a 4-year-old girl who presented with a 1-year history of iron deficiency anemia. Her hemoglobin level increased from 6.5 g/dL to 12.6 g/dL with a prolonged duration of therapeutic dose oral iron therapy (5 mg/kg/d), and the level remained quite stable during the therapy. Genetic analysis of the TMPRSS6 gene revealed compound heterozygotes of 2 novel pathogenic variants: c.811C> T (NM_153609.3) in exon 7 (NP_705837: p.R271Ter) and c.1254C> G in exon 11 (p.Y418Ter). The results highlight the significance of genetic investigation and long-term iron therapy in iron-refractory iron deficiency anemia patients.

Study the association of transmembrane serine protease 6 gene polymorphisms with iron deficiency status in Saudi Arabia

BACKGROUND

Intheclinical setting, iron deficiencyanaemia(IDA) represents a majorglobalhealthconcern. This health condition is reported in 30% of non-pregnant women, 42% of pregnant women (aged 15-50 years), 12.7% of men (15 years or older) and in 47% of preschool children (aged 0 to 5 years). Several genetic polymorphisms associated with iron status havebeen identified by using genome-wide association studies.

AIM

This study aimed to identify the functional polymorphismsrs855791 and rs2111833 in the transmembrane serine protease 6 (TMPRSS6) gene in female university students with IDA inthe Kingdom of Saudi Arabia.

METHODS

About 108 female students, aged from 18 to 25 years, were randomly selected and included to this study. Fifty-eightparticipants were iron deficient, and fifty participants were healthy. Blood samples were collected from all participants andassessed based on theirhaematologicaland biochemical iron status indices. Genotyping was carried out byusing PCR.

RESULTS

The genotype distribution oftheTMPRSS6rs855791 region in female studentsfromTabuk University,northern Saudi Arabia,was0% (CC), 77.6% (CT) and 22.4% (TT) in the iron-deficient students compared to 2% (CC), 96% (CT) and 2% (TT) in the healthy students,indicating significant differences in the allelic distribution betweentheiron-deficient group andthehealthy group. The genotype distribution of theTMPRSS6rs2111833 polymorphism was 8.6% (GG), 89.7% (GA) and 1.7% (AA) inthe iron-deficient students compared to 6% (GG), 92% (GA) and 2% (AA) in the healthy students,respectively,showing no differences between the iron-deficient group andthehealthy group in allelic distribution.

CONCLUSION

Our data demonstrated that theTMPRSS6 polymorphism rs855791 is significantly associated with decreased iron status, whereasTMPRSS6 polymorphismrs2111833 is not linked with iron deficiency status in female university students innorthern Saudi Arabia.