Encontrados 47 documentos, a visualizar página 1 de 5

The mitochondrial genome of the pinewood nematode (Bursaphelenchus xylophilus) ...

The pinewood nematode (PWN) Bursaphelenchus xylophilus is the causative agent of pine wilt disease and the greatest biological threat to conifer forests worldwide. Here we describe the near-complete mitochondrial DNA (mtDNA) sequence (12,945 bp) of the PWN lineage recently introduced in Europe. The absence of polymorphisms across the mtDNA of three Portuguese isolates suggests that a single mitochondrial lineag...

New Insights into the Phylogeny and Worldwide Dispersion of Two Closely Related...

The pinewood nematode, Bursaphelenchus xylophilus, is one of the greatest threats to coniferous forests worldwide, causing severe ecological damage and economic loss. The biology of B. xylophilus is similar to that of its closest relative, B. mucronatus, as both species share food resources and insect vectors, and have very similar morphological characteristics, although little pathogenicity to conifers has bee...

Human spermatogenic failure purges deleterious mutation load from the autosomes...

Gonadal failure, along with early pregnancy loss and perinatal death, may be an important filter that limits the propagation of harmful mutations in the human population. We hypothesized that men with spermatogenic impairment, a disease with unknown genetic architecture and a common cause of male infertility, are enriched for rare deleterious mutations compared to men with normal spermatogenesis. After assaying...

Validation of Rare Structural Variants in Portuguese Azoospermic Patients

Azoospermia affects approximately 15% of infertile males. Despite considerable research efforts in the last decades, in the majority of cases the cause remains unidentified. Chromosomal abnormalities and Yq microdeletions have been thoroughly studied, yet only account for 17% of azoospermic men. In fact, little is known about the contribution of the hemizygous X-linked and autosomal genes to male infertility. ...

Ancestral origin of the ATTCT repeat expansion in spinocerebellar ataxia type 1...

Spinocerebellar ataxia type 10 (SCA10) is an autosomal dominant neurodegenerative disease characterized by cerebellar ataxia and seizures. The disease is caused by a large ATTCT repeat expansion in the ATXN10 gene. The first families reported with SCA10 were of Mexican origin, but the disease was soon after described in Brazilian families of mixed Portuguese and Amerindian ancestry. The origin of the SCA10 expa...

Fragile X Syndrome: Genetic Backgrouds

Fragile X Syndrome (FXS) is the most frequent hereditary form of mental retardation, caused by an expansion of polymorphic [CGG] repeats in the 5’UTR region of the FMR1 gene; the molecular mechanism of this expansion is, however, still unknown. Based on [CGG] triplet number, three allele classes can be distinguished: normal sized-alleles (5-50 repeats); pre-mutation alleles (50-200 repeats) and the full mutatio...

Analysis of TPI gene promoter variation in three sub-Saharan Africa population ...

Population samples from Angola, Mozambique, and S. Tomé e Príncipe were screened for the TPI gene promoter variants -5ArarrG, -8GrarrA and -24TrarrG. Three haplotypes were identified in the three populations: the haplotype -5A-8G-24T (average frequency 65.3%) and two less common haplotypes -5G-8G-24T (average frequency 24.7%) and -5G-8A-24T (average frequency 10.0%). A population sample from Central Portugal sh...

Y-STR haplotype diversity in distinct linguistic groups from East Timor

East Timor is a country which harbors multiple ethnolinguistic groups generally assigned to an Austronesian or Papuan ancestry. The present study aimed to characterize Y-chromosome haplotype diversity in East Timor, and to test possible population structures based on linguistic and/or geographical information. Using a set of 12 Y-chromosome-specific STRs (DYS19, DYS389I and II, DYS390, DYS391, DYS392, DYS393, D...

Improving urban science education, new roles for teachers, students and researc...

Consórcios de bibliotecas no Brasil: um desafio à democratização do conhecimento

Discute o impacto da globalização eletrônica e a função desempenhada pelos consórcios de bibliotecas no Brasil, como um elemento de democratização do acesso à informação. Analisa o mercado de publicações científicas e descreve os principais consórcios de bibliotecas latino-americanas em anos recentes. Foi feito estudo de caso de um consórcio de bibliotecas brasileiras o - ProBE, seus benefícios para as bibliote...