[Demographic characteristics of Down's syndrome in Navarra. Trends of pre and postnatal diagnosis for the period 1991-2009]. / Caracteristicas demograficas del sindrome de Down en Navarra. evolucion del diagnostico pre y postnatal durante el periodo 1991-2009.

This study describes the development of pre and postnatal diagnosis of sindrome de Down (SD) in the Autonomous Community of Navarre from 1991 to 2009 and assesses its preventive impact in the population, as well as to associated socio-demographic changes. In the absence of a prenatal diagnosis for DS, the change in maternal age from 1991 to 2009 would have caused a 50% increase in births with this disorder. However, the antenatal rate detection of DS increased from 15.8% in 1991-4 to 64.3% in 2006-9, giving rise to a decreasing incidence trend, not statistically significant, during the study period and to a higher mean age of mothers of live births with DS (32.75± 5,02 and 34.8±4,82 years during the first and second periods of the study, respectively). The proportion of young mothers (<35 years) of live births with DS was 66% in 1991-4 and 45% in 2006-9. Close to one fifth of the total population of pregnant women, however, did not want to go through a maternal screening test or amniocentesis. Seventeen per cent of all live births with DS had a positive screening test, but mothers decided to continue pregnancy. These results suggest that, despite the application of new and more sensitive prenatal screening tests, the incidence of DS may still be relatively high in our population, an important factor to be considered for future antenatal preventive programs and adequate postnatal care.

Características demográficas del síndrome de Down en Navarra. Evolución del diagnóstico pre y postnatal durante el periodo 1991-2009 / Demographic characteristics of Down´s syndrome in Navarra. Trends of pre and postnatal diagnosis for the period 1991-2009

Este estudio describe la evolución del diagnóstico pre y postnatal del síndrome de Down (SD) en la Comunidad Foral de Navarra desde 1991 a 2009 y analiza su impacto preventivo a nivel poblacional, así como los cambios asociadas a dicha cromosomopatía. En ausencia de diagnóstico prenatal del SD, el cambio en la edad materna desde 1991 a 2009 hubiera conllevado un aumento del 50% en el número de nacimientos con esta cromosomopatía. Sin embargo, el incremento de la tasa de detección prenatal (15,8% durante 1991-1994 y 64,3% entre 2006-2009) ha condicionado una ligera tendencia descendiente de su prevalencia al nacimiento, no estadísticamente significativa, y un aumento en la edad media de sus madres (32,75± 5,02 y 34,8±4,82 años en el primer y último periodos, respectivamente). El porcentaje de SD nacidos vivos, hijos de madres menores de 35 años, fue del 66% en 1991-2004 y del 45% en 2006-2009. Casi una quinta parte de las gestantes rechazaron el cribado bioquímico o la amniocentesis y un 17% de los nacimientos con SD tuvieron un resultado de cribado positivo, pero las madres decidieron continuar el embarazo. Estos resultados sugieren que, a pesar de implementar nuevos y más sensibles test de cribado, la incidencia del SD puede mantenerse relativamente alta en nuestra población, circunstancia a tener en cuenta tanto en la elaboración de los planes de prevención antenatal como de los de su cuidado postnatal (AU)

This study describes the development of pre and postnatal diagnosis of sindrome de Down (SD) in the Autonomous Community of Navarre from 1991 to 2009 and assesses its preventive impact in the population, as well as to associated socio-demographic changes. In the absence of a prenatal diagnosis for DS, the change in maternal age from 1991 to 2009 would have caused a 50% increase in births with this disorder. However, the antenatal rate detection of DS increased from 15.8% in 1991-4 to 64.3% in 2006-9, giving rise to a decreasing incidence trend, not statistically significant, during the study period and to a higher mean age of mothers of live births with DS (32.75± 5,02 and 34.8±4,82 years during the first and second periods of the study, respectively).The proportion of young mothers (<35 years) of live births with DS was 66% in 1991-4 and 45% in 2006-9. Close to one fifth of the total population of pregnant women, however, did not want to go through a maternal screening test or amniocentesis. Seventeen per cent of all live births with DS had a positive screening test, but mothers decided to continue pregnancy. These results suggest that, despite the application of new and more sensitive prenatal screening tests, the incidence of DS may still be relatively high in our population, an important factor to be considered for future antenatal preventive programs and adequate postnatal care (AU)

Síndrome de Aarskog-Scott. A propósito de un caso con identificación molecular de la mutación génica / Aarskog-Scott syndrome. About a case report with molecular identification of the gene mutation

El síndrome de Aarskog-Scott, o displasia faciodigitogenital, fue descrito en 1970 por Aarskog. Es una entidad con herencia recesiva ligada al cromosoma X, con una amplia heterogeneidad genética, ya que se han descrito casos compatibles con la transmisión autosómica dominante o semidominante ligada al cromosoma X con expresión parcial en mujeres portadoras. Presentamos el caso de un paciente con datos clínicos compatibles con esta entidad, así como el estudio molecular realizado en él y en su madre, en quienes se encuentra una mutación (c.527insC) en el exón 3 del gen FGD1 (Xp11.21). Las mutaciones referidas hasta la fecha son específicas de un caso particular o familiar. Es importante conocer las diferentes mutaciones encontradas en las distintas poblaciones para intentar establecer una relación genotipo-fenotipo (AU)

The Aarskog-Scott syndrome (SAS) or faciodigitogenital dysplasia was described in 1970 by Aarskog. It is an entity with recessive heredity bond to X with broad genetic heterogeneity as compatible cases are with dominant or semi dominant autosomal transmission bond to X with partial expression in female carriers. We describe a patient with clinical data compatible to the entity and the molecular study performed to him and to his mother in which there is a mutation (c.527insC) in exon 3 of FGD1 gene (Xp11.21). The mutations known up to date are specific of a particular or family case. It is important to know the different mutations identified in different populations to try determining a phenotype-genotype relation (AU)

Modifying effect of HLA haplotypes located trans to DQB1*02-DRB1*03 in celiac patients of Southern Europe.

The DQ2 heterodimer, encoded by the human leukocyte antigen (HLA)-DQA1*05-DQB1*02 alleles, is the major genetic susceptibility factor for celiac disease (CD). However, the risk associated to HLA alleles varies among populations. While DRB1*03 is almost the only CD susceptibility allele in Northern Europe with a homozygote frequency of around 30%, CD in south European countries is also associated with the DRB1*07, and DRB1*03 homozygotes patients are rare. Some authors have suggested that DQB1*02-DRB1*03/DQB1*02-DRB1*03 and DQB1*02-DRB1*03/DQB1*02-DRB1*07 may confer different risk susceptibility to CD. This hypothesis, however, has not been demonstrated in a recent family-based study carried out in Finland, suggesting that the proposed differences in risk may be secondary to stratification burdens of case-control studies. To assess this issue, we have investigated the effect of different haplotypes carried trans to DQB1*02-DRB1*03 as additional factors for CD in Spain, using two statistical approaches, a case-control study and a family-based study. We found that DQB1*02-DRB1*03/DQB1*02-DRB1*03 and DQB1*02-DRB1*03/DQB1*02-DRB1*07 were the only combinations that showed a strong and independent association to CD. We did not observe any difference in susceptibility risk conferred by DQB1*02-DRB1*03 and DQB1*02-DRB1*07 when carried trans to DQB1*02-DRB1*03, suggesting that variation in HLA haplotype frequencies among populations may not represent real differences in risk to CD development. We also confirmed a gene dosage effect of the DQB1*02-DRB1*03 haplotype estimating that DQB1*02 homozygotes are at fivefold increased risk for CD compared with DQB1*02 heterozygotes. This risk is conferred by the second copy of the DQB1*02 allele and it seems to be independent of the DQA1.