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Cabral R.,Molecular Genetics and Pathology Unit | Pires R.,Molecular Genetics and Pathology Unit | Pires R.,University of Lisbon | Anjos R.,Hospital of Santa Cruz | And 7 more authors.
Annals of Human Biology | Year: 2015

Background: Congenital heart disease (CHD) is one common birth malformation, accounting for ∼30% of total congenital abnormalities. Aim: Considering the unknown role of consanguinity in causing CHD, this study hypothesised that consanguineous unions and/or familial aggregation may be frequent in the Azorean Island of São Miguel (Portugal). To that end, a retrospective observational study was performed based on genealogical and molecular analyses. Subjects and methods: The study enrolled 112 CHD patients from São Miguel Island, which allowed the assessment of type of family (simplex or multiplex), parental consanguinity and grandparental endogamy. Based on 15 STR markers, inbreeding coefficients (FIS) in the CHD cohort and healthy control group (n = 114) were estimated. Results: Multiplex families were 37.6% (n = 41/109), a rate considerably higher than previously described in the literature (< 15%). Moreover, 9.2% (n = 10/109) of the CHD families were consanguineous, mostly derived from third cousin unions, and 20.2% (n = 22/109) presented full grandparental endogamy. Higher FIS values were found in patients with parental consanguinity (0.0371) and patent ductus arteriosus (0.0277). Conclusion: This study analysed several genealogical and genetic features related with CHD, revealing the presence of parental consanguinity and extensive familial aggregation in the CHD patients from São Miguel Island. © 2015 Taylor & Francis.

Melo B.C.S.,Hospital of Divino Espirito Santo of Ponta Delgada | Portocarrero A.,Genetica Medica e Diagnostico Pre Natal Professor Doutor Sergio Castedo | Alves C.,Genetica Medica e Diagnostico Pre Natal Professor Doutor Sergio Castedo | Sampaio A.,Hospital of Divino Espirito Santo of Ponta Delgada | And 3 more authors.
Clinical Medicine Insights: Case Reports | Year: 2015

The detection of supernumerary marker chromosomes (SMCs) in prenatal diagnosis is always a challenge. In this study, we report a paternally inherited case of a small SMC(15) that was identified in prenatal diagnosis due to advanced maternal age. A 39-year-old woman underwent amniocentesis at 16 weeks of gestation. A fetal abnormal karyotype – 47,XX,+mar – with one sSMC was detected in all metaphases. Since this sSMC was critical in the parental decision to continue or interrupt this pregnancy, we proceeded to study the fetus and their parents. Cytogenetic and molecular analyses revealed a fetal karyotype 47,XX,+mar pat.ish idic(15)(ql2)(D15Zl++,SNRPN−), in which the sSMC(15) was a paternally inherited inverted duplicated chromosome and did not contain the critical region of Prader–Willi/Angelman syndromes. Moreover, fetal uniparental disomy was excluded. Based on this information and normal obstetric ultrasounds, the parents decided to proceed with the pregnancy and a phenotypically normal girl was born at 39 weeks of gestation. In conclusion, the clinical effects of sSMCs need to be investigated, especially when sSMCs are encountered at prenatal diagnosis. Here, although the paternal sSMC(15) was not associated with an abnormal phenotype, its characterization allows more accurate genetic counseling for the family progeny. © the authors, publisher and licensee Libertas Academica Limited.

Vaz S.O.,Hospital of Divino Espirito Santo of Ponta Delgada | Pires R.,Molecular Genetics and Pathology Unit | Pires R.,University of Lisbon | Pires L.M.,University of Coimbra | And 6 more authors.
BMC Pediatrics | Year: 2015

Background: The rearrangements of the 22q11.2 chromosomal region, most frequently deletions and duplications, have been known to be responsible for multiple congenital anomaly disorders. These rearrangements are implicated in syndromes that have some phenotypic resemblances. While the 22q11.2 deletion, also known as DiGeorge/Velocardiofacial syndrome, has common features that include cardiac abnormalities, thymic hypoplasia, characteristic face, hypocalcemia, cognitive delay, palatal defects, velopharyngeal insufficiency, and other malformations, the microduplication syndrome is largely undetected. This is mainly because phenotypic appearance is variable, milder, less characteristic and unpredictable. In this paper, we report the clinical evaluation and follow-up of two patients affected by 22q11.2 rearrangements, emphasizing new phenotypic features associated with duplication and triplication of this genomic region. Case Presentation: Patient 1 is a 24 year-old female with 22q11.2 duplication who has a heart defect (ostium secundum atrial septal defect) and supernumerary teeth (hyperdontia), a feature previously not reported in patients with 22q11.2 microduplication syndrome. Her monozygotic twin sister, who died at the age of one month, had a different heart defect (truncus arteriousus). Patient 2 is a 20 year-old female with a 22q11.2 triplication who had a father with 22q11.2 duplication. In comparison to the first case reported in the literature, she has an aggravated phenotype characterized by heart defects (restrictive VSD and membranous subaortic stenosis), and presented other facial dysmorphisms and urogenital malformations (ovarian cyst). Additionally, she has a hemangioma planum on the right side of her face, a feature of Sturge-Weber syndrome. Conclusions: In this report, we described hyperdontia as a new feature of 22q11.2 microdeletion syndrome. Moreover, this syndrome was diagnosed in a patient who had a deceased monozygotic twin affected with a different heart defect, which corresponds to a phenotypic discordance never reported in the literature. Case 2 is the second clinical report of 22q11.2 triplication and presents an aggravated phenotype in contrast to the patient previously reported. © 2015 Vaz et al.

Esteves L.M.,Molecular Genetics and Pathology Unit | Bulhoes S.M.,Molecular Genetics and Pathology Unit | Branco C.C.,Molecular Genetics and Pathology Unit | Branco C.C.,Instituto Gulbenkian Of Ciencia | And 9 more authors.
PLoS ONE | Year: 2014

Background: Leptospirosis is a worldwide zoonotic and recognized neglected infectious disease. It has been observed that only a proportion of individuals exposed to pathogenic species of Leptospira become infected and develop clinically evident disease. Moreover, little information is available in subsequent reinfections. In the present study, we determine if a first infection with leptospirosis protects against subsequent reinfection, and investigate which of the host genetic factors are involved in the susceptibility and resistance to leptospirosis.Methodology and Findings: We conducted, in 2011, a retrospective hospital-based case-control study in the São Miguel Island population (Azores archipelago). In order to determine the seropositivity against pathogenic Leptospira after the first episode of leptospirosis, we performed a serological evaluation in 97 unrelated participants diagnosed with leptospirosis between 1992 and 2011. The results revealed that 46.4% of the 97 participants have circulating anti-Leptospira antibodies, and from these participants 35.6% maintained the seroprevalence for the same serogroup. Moreover, three of them were reinfected with unrelated Leptospira serovars. The genetic study was carried out by adding a control group composed of 470 unrelated healthy blood donors, also from São Miguel Island. Twenty five SNPs among twelve innate immune genes - IL1α, IL1β, IL6, IL10, IL12RB1, TLR2, TLR4, TLR9, CD14, CISH, LTA and TNF - were genotyped, as well as HLA class I (-A and -B) genes. Association analysis indicates that genotypes -511GG (OR= 1.6, 95%CI 1.01-2.56, p = 0.04) in IL1β, +1196CG (OR = 2.0, 95%CI 1.26-3.27, p = 0.003) in IL12RB1, -292TA (OR= 1.8, 95% CI 1.06-2.1, p = 0.03) and +3415CG (OR= 1.8, 95% CI 1.08-3.08, p = 0.02), both in CISH confer susceptibility to pathogenic Leptospira.Conclusion: The present study suggests some degree of long-term protection against leptospires with an attenuation of symptoms in case of reinfection. Moreover, our data supports the genetic influence of IL1β, IL12RB1 and CISH genes and the susceptibility to leptospirosis infection. © 2014 Esteves et al.

Branco C.C.,Molecular Genetics and Pathology Unit | Branco C.C.,Instituto Gulbenkian Of Ciencia | Branco C.C.,University of Lisbon | Gomes C.T.,Molecular Genetics and Pathology Unit | And 13 more authors.
PLoS ONE | Year: 2015

Iron overload is associated with acquired and genetic conditions, the most common being hereditary hemochromatosis (HH) type-I, caused by HFE mutations. Here, we conducted a hospital-based case-control study of 41 patients from the Sao Miguel Island (Azores, Portugal), six belonging to a family with HH type-I pseudodominant inheritance, and 35 unrelated individuals fulfilling the biochemical criteria of iron overload compatible with HH type-I. For this purpose, we analyzed the most common HFE mutations. c.845G>A [p.Cys282Tyr], c.187C>G [p.His63Asp], and c.193A>T [p.Ser65Cys]. Results revealed that the family's HH pseudodominant pattern is due to consanguineous marriage of HFE-c.845G>A carriers, and to marriage with a genetically unrelated spouse that is a -c.187G carrier. Regarding unrelated patients, six were homozygous for c.845A, and three were c.845A/c.187G compound heterozygous. We then performed sequencing of HFE exons 2, 4, 5 and their intronflanking regions. No other mutations were observed, but we identified the -c.340+4C [IVS2 +4C] splice variant in 26 (74.3%) patients. Functionally, the c.340+4C may generate alternative splicing by HFE exon 2 skipping and consequently, a protein missing the ¿1-domain essential for HFE/transferrin receptor-1 interactions. Finally, we investigated HFE mutations configuration with iron overload by determining haplotypes and genotypic profiles. Results evidenced that carriers of HFE-c.187G allele also carry -c.340+4C, suggesting incis configuration. This data is corroborated by the association analysis where carriers of the complex allele HFE-c.[187C>G;340+4T>C] have an increased iron overload risk (RR = 2.08, 95% CI =, p<0.001). Therefore, homozygous for this complex allele are at risk of having iron overload because they will produce two altered proteins-the p.63Asp [c.187G], and the protein lacking 88 amino acids encoded by exon 2. In summary, we provide evidence that the complex allele HFE-c.[187C>G;340+4T>C] has a role, as genetic predisposition factor, on iron overload in the São Miguel population. Independent replication studies in other populations are needed to confirm this association. © 2015 Branco et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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