Background: Vitamin B12 (cobalamin) deficiency is a prevalent worldwide health concern. Several factors are associated with vitamin B12 deficiency including lifestyle, genetic predisposition, and malfunctions in the absorption and transport of vitamin B12. In the current case-control study, we aimed at investigating the association between MTHFR polymorphisms and vitamin B12 deficiency in a Jordanian population.
Methods: Two polymorphic sites of the MTHFR gene (c.677C>T, rs1801133 and c.1286A>C, rs1801131) were analyzed using RFLP and DNA sequencing in a group of vitamin B12 deficient individuals (45 males and 55 females). As a control, 100 matching individuals (age and sex) with vitamin B12 levels > 200 ng/mL were also recruited for this study.
Results: The MTHFR c.677C>T variant was significantly associated with vitamin B12 deficiency in individuals from northern Jordan. The frequency of the homozygous MTHFR c.677C>T genotype was significantly higher in B12 deficient individuals in comparison with the control group (X2 = 8.397, p = 0.0150). The T allele frequency showed significant association with vitamin B12 deficiency in the study population (OR= 1.684, 95% CI: 1.116 to 2.542, p = 0.017). On the other hand, the MTHFR c.1286A>C variant did not show significant association with vitamin B12 deficiency in the selected population.
Conclusions: Our results showed a significant association between homozygous MTHFR c.677C>T variant and T allele frequencies and vitamin B12 deficiency in the Jordanian population.
Uvod: Nedostatak vitamina B12 (kobalamina) predstavlja svetski rasprostranjen zdravstveni problem. Sa deficijencijom vitamina B12 povezano je nekoliko faktora, kao što su način života, genetska predispozicija i poteškoće u apsorpciji i transportu vitamina B12. U ovoj anamnestičkoj studiji, cilj nam je bio da istražimo povezanost između polimorfizama MTHFR i deficijencije vitamina B12 u jednoj populaciji Jordanaca.
Metode: Dva polimorfna mesta na genu MTHFR (c.677C>T, rs1801166 i c.1286A>C, rs1801131) analizirana su pomoću metoda RFLP i DNK sekvenciranja u grupi sa deficijencijom vitamina B12 (45 muškaraca i 55 žena). Kao kontrolna grupa, u ovu studiju takođe je uključeno 100 osoba odgovarajuće starosti i pola sa nivoima vitamina B12 > 200 ng/mL.
Rezultati: Otkrivena je značajna povezanost između varijante MTHFR c.677C>T i deficijencije vitamina B12 kod osoba iz severnog Jordana. Učestalost homozigotnog genotipa MTHFR c.677C>T bila je značajno veća kod osoba sa nedostatkom B12 u poređenju s kontrolnom grupom (X2=8,397, p=0,0150). Učestalost T alela ukazala je na značajnu povezanost sa deficijencijom vitamina B12 u proučavanoj populaciji (OR = 1,684, 95% CI: 1,116 do 2,542, p = 0,017). S druge strane, varijanta MTHFR c.1286A>C nije bila u značajnoj asocijaciji s nedostatkom vitamina B12 u izabranoj populaciji.
Zaključak: Naši rezultati ukazuju na značajnu povezanost između učestalosti homozigotnih MTHFR c.677C>T i T alela i deficijencije vitamina B12 u ovoj populaciji Jordanaca.
Keywords: MTHFR polymorphisms; folate metabolism; homocysteine; vitamin B12 deficiency.