Four variants in transferrin and HFE genes as potential markers of iron deficiency anaemia risk: an association study in menstruating women

Abstract Background Iron deficiency anaemia is a worldwide health problem in which environmental, physiologic and genetic factors play important roles. The associations between iron status biomarkers and single nucleotide polymorphisms (SNPs) known to be related to iron metabolism were studied in menstruating women. Methods A group of 270 Caucasian menstruating women, a population group at risk of iron deficiency anaemia, participated in the study. Haematological and biochemical parameters were analysed and 10 selected SNPs were genotyped by minisequencing assay. The associations between genetic and biochemical data were analysed by Bayesian Model Averaging (BMA) test and decision trees. Dietary intake of a representative subgroup of these volunteers (n = 141) was assessed, and the relationship between nutrients and iron biomarkers was also determined by linear regression. Results Four variants, two in the transferrin gene (rs3811647, rs1799852) and two in the HFE gene (C282Y, H63D), explain 35% of the genetic variation or heritability of serum transferrin in menstruating women. The minor allele of rs3811647 was associated with higher serum transferrin levels and lower transferrin saturation, while the minor alleles of rs1799852 and the C282Y and H63D mutations of HFE were associated with lower serum transferrin levels. No association between nutrient intake and iron biomarkers was found. Conclusions In contrast to dietary intake, these four SNPs are strongly associated with serum transferrin. Carriers of the minor allele of rs3811647 present a reduction in iron transport to tissues, which might indicate higher iron deficiency anaemia risk, although the simultaneous presence of the minor allele of rs1799852 and HFE mutations appear to have compensatory effects. Therefore, it is suggested that these genetic variants might potentially be used as markers of iron deficiency anaemia risk.This study was supported by Project AGL2009-11437. R.Blanco-Rojo was supported by a JAE-predoc grant from CSIC and European Social Found, S.Bertoncini by Grupo Santander 2009 (Estancia doctores y tecnologos UCM), and J.M.Soria by "Programa d'Estabilització d'Investigadors de la Direcció d'Estrategia i Coordinació del Departament de Salut".Peer Reviewe

Phenotyping the ancient world: the physical appearance and ancestry of very degraded samples from a chalcolithic human remains

The genetic study of ancient samples is quite similar to a forensic critical sample analysis with an unknown origin. In both cases, it is not possible to compare the genetic information with other family members, being almost impossible to achieve the individual identification. The prediction of externally visible characteristics (EVC) of an individual and his biogeographical ancestry could definitely be a crucial contribution in a forensic casework. Therefore, the aim of the present work was the molecular study of a very critical sample, a Chalcolithic (3480 ± 30 YBP) individual found in Asturias, Northern Iberia, intending to discover a possible geographical ancestry for these remains, and the inference of a group of feasible EVCs (hair, skin and iris pigmentation). Given that ancient DNA is often highly damaged, two different methodologies were used in order to determine the biogeographical ancestry of the individual: mitochondrial DNA (HVR-I and -II) and Single Nucleotide Polymorphisms typing. Despite the antiquity of the samples, the genetic information recovered proved of great value. We could determine that the individual had a European ancestry, blond hair, light skin color and brown eyes. Such outcome reveals that it is possible to obtain not only biogeographical but also phenotypic information from a very critical sample

Acenocoumarol Pharmacogenetic Dosing Algorithm versus Usual Care in Patients with Venous Thromboembolism: A Randomised Clinical Trial

Patients with venous thromboembolism (VTE) require immediate treatment with anticoagulants such as acenocoumarol. This multicentre randomised clinical trial evaluated the effectiveness of a dosing pharmacogenetic algorithm versus a standard-of-care dose adjustment at the beginning of acenocoumarol treatment. We included 144 patients with VTE. On the day of recruitment, a blood sample was obtained for genotyping (CYP2C9*2, CYP2C9*3, VKORC1, CYP4F2, APOE). Dose adjustment was performed on day 3 or 4 after the start of treatment according to the assigned group and the follow-up was at 12 weeks. The principal variable was the percentage of patients with an international normalised ratio (INR) within the therapeutic range on day 7. Thirty-four (47.2%) patients had an INR within the therapeutic range at day 7 after the start of treatment in the genotype-guided group compared with 14 (21.9%) in the control group (p = 0.0023). There were no significant differences in the time to achieve a stable INR, the number of INRs within the range in the first 6 weeks and at the end of study. Our results suggest the use of a pharmacogenetic algorithm for patients with VTE could be useful in achieving target INR control in the first days of treatment

Second GHEP-ISFG exercise for DVI: “DNA-led” victims’ identification in a simulated air crash

The Spanish and Portuguese-Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) has organized a second collaborative exercise on a simulated case of Disaster Victim Identification (DVI), with the participation of eighteen laboratories. The exercise focused on the analysis of a simulated plane crash case of medium-size resulting in 66 victims with varying degrees of fragmentation of the bodies (with commingled remains). As an additional difficulty, this second exercise included 21 related victims belonging to 6 families among the 66 missings to be identified. A total number of 228 post-mortem samples were represented with aSTR and mtDNA profiles, with a proportion of partial aSTR profiles simulating charred remains. To perform the exercise, participants were provided with aSTR and mtDNA data of 51 reference pedigrees —some of which deficient—including 128 donors for identification purposes. The exercise consisted firstly in the comparison of the post-mortem genetic profiles in order to re-associate fragmented remains to the same individual and secondly in the identification of the re-associated remains by comparing aSTR and mtDNA profiles with reference pedigrees using pre-established thresholds to report a positive identification. Regarding the results of the post-mortem samples re-associations, only a small number of discrepancies among participants were detected, all of which were from just a few labs. However, in the identification process by kinship analysis with family references, there were more discrepancies in comparison to the correct results. The identification results of single victims yielded fewer problems than the identification of multiple related victims within the same family groups. Several reasons for the discrepant results were detected: a) the identity/non-identity hypotheses were sometimes wrongly expressed in the likelihood ratio calculations, b) some laboratories failed to use all family references to report the DNA match, c) In families with several related victims, some laboratories firstly identified some victims and then unnecessarily used their genetic information to identify the remaining victims within the family, d) some laboratories did not correctly use “prior odds” values for the Bayesian treatment of the episode for both post-mortem/post-mortem re-associations as well as the ante-mortem/post-mortem comparisons to evaluate the probability of identity. For some of the above reasons, certain laboratories failed to identify some victims. This simulated “DNA-led” identification exercise may help forensic genetic laboratories to gain experience and expertize for DVI or MPI in using genetic data and comparing their own results with the ones in this collaborative exercise.This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.Peer reviewe

Estudio de asociación entre marcadores genéticos y alteraciones del metabolismo del hierro en población española

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Biológicas, Departamento de Zoología y Antropología Física, leída el 14-12-2015.Depto. de Biodiversidad, Ecología y EvoluciónFac. de Ciencias BiológicasTRUEunpu

Second GHEP-ISFG exercise for DVI: "DNA-led" victims' identification in a simulated air crash

The Spanish and Portuguese-Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) has organized a second collaborative exercise on a simulated case of Disaster Victim Identification (DVI), with the participation of eighteen laboratories. The exercise focused on the analysis of a simulated plane crash case of medium-size resulting in 66 victims with varying degrees of fragmentation of the bodies (with commingled remains). As an additional difficulty, this second exercise included 21 related victims belonging to 6 families among the 66 missings to be identified. A total number of 228 post-mortem samples were represented with aSTR and mtDNA profiles, with a proportion of partial aSTR profiles simulating charred remains. To perform the exercise, participants were provided with aSTR and mtDNA data of 51 reference pedigrees -some of which deficient-including 128 donors for identification purposes. The exercise consisted firstly in the comparison of the post-mortem genetic profiles in order to re-associate fragmented remains to the same individual and secondly in the identification of the re-associated remains by comparing aSTR and mtDNA profiles with reference pedigrees using pre-established thresholds to report a positive identification. Regarding the results of the post-mortem samples re-associations, only a small number of discrepancies among participants were detected, all of which were from just a few labs. However, in the identification process by kinship analysis with family references, there were more discrepancies in comparison to the correct results. The identification results of single victims yielded fewer problems than the identification of multiple related victims within the same family groups. Several reasons for the discrepant results were detected: a) the identity/non-identity hypotheses were sometimes wrongly expressed in the likelihood ratio calculations, b) some laboratories failed to use all family references to report the DNA match, c) In families with several related victims, some laboratories firstly identified some victims and then unnecessarily used their genetic information to identify the remaining victims within the family, d) some laboratories did not correctly use "prior odds" values for the Bayesian treatment of the episode for both post-mortem/post-mortem re-associations as well as the ante-mortem/post-mortem comparisons to evaluate the probability of identity. For some of the above reasons, certain laboratories failed to identify some victims. This simulated "DNA-led" identification exercise may help forensic genetic laboratories to gain experience and expertize for DVI or MPI in using genetic data and comparing their own results with the ones in this collaborative exercise.Depto. de Medicina Legal, Psiquiatría y PatologíaFac. de MedicinaTRUEpu

Influence of diet, menstruation and genetic factors on iron status: A cross-sectional study in Spanish women of childbearing age

The aim of this study was to investigate the combined influence of diet, menstruation and genetic factors on iron status in Spanish menstruating women (n = 142). Dietary intake was assessed by a 72-h detailed dietary report and menstrual blood loss by a questionnaire, to determine a Menstrual Blood Loss Coefficient (MBLC). Five selected SNPs were genotyped: rs3811647, rs1799852 (Tf gene); rs1375515 (CACNA2D3 gene); and rs1800562 and rs1799945 (HFE gene, mutations C282Y and H63D, respectively). Iron biomarkers were determined and cluster analysis was performed. Differences among clusters in dietary intake, menstrual blood loss parameters and genotype frequencies distribution were studied. A categorical regression was performed to identify factors associated with cluster belonging. Three clusters were identified: women with poor iron status close to developing iron deficiency anemia (Cluster 1, n = 26); women with mild iron deficiency (Cluster 2, n = 59) and women with normal iron status (Cluster 3, n = 57). Three independent factors, red meat consumption, MBLC and mutation C282Y, were included in the model that better explained cluster belonging (R2 = 0.142, p < 0.001). In conclusion, the combination of high red meat consumption, low menstrual blood loss and the HFE C282Y mutation may protect from iron deficiency in women of childbearing age. These findings could be useful to implement adequate strategies to prevent iron deficiency anemia. © 2014 by the authors; licensee MDPI, Basel, Switzerland.This study was supported by Project AGL2009-11437.We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).Peer Reviewe

A novel snapshot assay to detect genetic mutations related to iron metabolism

7 páginas.The minisequencing method is a cost-effective tool to study single-nucleotide polymorphisms in human disease. For this reason, a novel polymerase chain reaction multiplex SNaPshot reaction has been developed that targets 10 autosomal mutations in genes, or regions near to them, reported to be involved in iron metabolism: TMPRSS6, TF, and HFE. To validate this multiplex, 284 samples from unrelated women from the Spanish population were tested at a fertile age. The novel polymerase chain reaction multiplex SNaPshot reaction developed is a very simple, sensitive, and low-cost approach, and therefore will be useful as a tool of clinic diagnosis in iron metabolism alterations and to replicate results obtained from genome-wide linkage analysis.Peer reviewe

Genetic contribution to iron status: SNPs related to iron deficiency anaemia and fine mapping of CACNA2D3 calcium channel subunit

© 2015 Elsevier Inc. Numerous studies associate genetic markers with iron- and erythrocyte-related parameters, but few relate them to iron-clinical phenotypes. Novel SNP rs1375515, located in a subunit of the calcium channel gene CACNA2D3, is associated with a higher risk of anaemia. The aim of this study is to further investigate the association of this SNP with iron-related parameters and iron-clinical phenotypes, and to explore the potential role of calcium channel subunit region in iron regulation. Furthermore, we aim to replicate the association of other SNPs reported previously in our population. We tested 45 SNPs selected via systematic review and fine mapping of CACNA2D3 region, with haematological and biochemical traits in 358 women of reproductive age. Multivariate analyses include back-step logistic regression and decision trees. The results replicate the association of SNPs with iron-related traits, and also confirm the protective effect of both A allele of rs1800562 (HFE) and G allele of rs4895441 (HBS1L- MYB). The risk of developing anaemia is increased in reproductive age women carriers of A allele of rs1868505 (CACNA2D3) and/or T allele of rs13194491 (HIST1H2BJ). Association of SNPs from fine mapping with ferritin and serum iron suggests that calcium channels could be a potential pathway for iron uptake in physiological conditions.This study was supported by projects GR35/10 and AGL2009-11437.Peer Reviewe

Spanish allele and haplotype database for 32 X-chromosome Insertion-Deletion polymorphisms

X-chromosome markers have been proved to be decisive both complementing and solving kinship analysis, particularly when autosomal markers are not able to produce adequate likelihood ratios between different hypothesis. On the other hand, Pereira et al., (2012) have demonstrated that 32 Insertion/Deletion (InDel) markers located on the X-Chromosome have a very important power of discrimination in human populations, being a novel tool in the forensic and population fields. So, the aim of the present work was testing the forensic and population genetic efficiency of the 32 X-InDel polymorphisms in the Spanish population, and subsequently build an allele/haplotype frequencies database. To accomplish this objective, a total of 555 samples comprising male individuals from 13 Spanish regions were analysed for the above mentioned 32 X-InDels in two independent laboratories. A pairwise FST analysis was performed in order to understand if the studied Spanish sub-populations present significant differences among them, detecting possible population substructure. Also, linkage disequilibrium analyses were computed to investigate the presence of association between markers in the Spanish population. After Bonferroni correction, the absence of significant differences among the studied regions supports a global Spanish population database. Concerning LD, besides previously reported linked markers MID356-MID357 and MID3690-MID3719-MID2089, we also detected significant association between MID3703-MID3774, even after Bonferroni correction. Finally, after computing allele and haplotype frequencies, forensic efficiency parameters were calculated (PDmales = 99.999976 %; PDfemales = 99.99999999998 %). Mean exclusion chance values for duos were 0.999 and trios 0.99999. These results reinforce the suitability of the 32 X-InDels marker set both in identification and kinship studies.Santander-Universidad Complutense de MadridMINECODepto. de Medicina Legal, Psiquiatría y PatologíaFac. de MedicinaTRUEpu