Diet and Leukocyte Telomere Length in a Population with Extended Longevity: The Costa Rican Longevity and Healthy Aging Study (CRELES).

Elderly Costa Ricans have lower mortality rates compared to their counterparts from developed countries. Reasons for this survival advantage are not completely known. In the present study, we aimed to identify dietary factors associated with leukocyte telomere length (LTL), a marker of biologic aging, in the elderly population of Costa Rica.

Correlates of longitudinal leukocyte telomere length in the Costa Rican Longevity Study of Healthy Aging (CRELES): On the importance of DNA collection and storage procedures.

The objective is to identify cofactors of leukocyte telomere length (LTL) in a Latin American population, specifically the association of LTL with 36 socio-demographic, early childhood, and health characteristics, as well as with DNA sample collection and storage procedures. The analysis is based on longitudinal information from a subsample of 1,261 individuals aged 60+ years at baseline from the Costa Rican Study of Longevity and Healthy Aging (CRELES): a nationally representative sample of elderly population. Random effects regression models for panel data were used to estimate the associations with LTL and its longitudinal changes.

Amerindian ancestry and extended longevity in Nicoya, Costa Rica.

Objectives: The aim of this study was to address the hypothesis that Amerindian ancestry is associated with extended longevity in the admixed population of Nicoya, Costa Rica. The Nicoya Peninsula of Costa Rica has been considered a "longevity island," particularly for males.

Methods: We estimated Amerindian ancestry using 464 ancestral informative markers in 20 old Nicoyans aged ≥99 years, and 20 younger Nicoyans (60-65 years).

The STR polymorphism (AAAAT)n within the intron 1 of the tumor protein 53 (TP53) locus in 17 populations of different ethnic groups of Africa, America, Asia and Europe.

The STR (AAAAT)n within intron 1 of the TP53 locus was screened in 17 populations from 3 main ethnic groups: Europeans, Asiatics, and Africans, and from the hybrid population of Costa Rica (1968 samples). Three alleles, 126/7 (bp/copies of the repeat), 131/8 and 136/9 were the most prevalent in all populations. Other alleles rarely reached frequencies of 10% or higher.

Glaucoma in Costa Rica. Initial approaches.

Glaucoma is the second most frequent cause of irreversible blindness worldwide. Genetic factors have been implicated in the development of the disease. So far six loci (GLC1A-GLC1F) and two genes (TIGR/MYOC and OPTN) are involved in the development of juvenile (JOAG) and adult onset or chronic primary open angle glaucoma (COAG), while two loci (GLC3A,GLC3B) and one gene (CYP1B1) are known for primary congenital glaucoma (PCG).

The dystrophinopathies in Costa Rica.

A five-years long study aiming to describe the basic genetic epidemiology of the dystrophinopathies in Costa Rica recruited 31 patients with clinical symptoms of DMD/BMD at the National Children's Hospital (HNN). This center is the obligate reference hospital of the national health system for genetic diseases, however, the geographic origin of the patients, a low percentage of deletions and a high proportion of de novo mutations found among them indicate that a significant ascertainment bias impedes a substantial scientific approach to confront and alleviate the problems posed by these severe diseases in Costa Rica.

Genetic variation of the Y chromosome in Chibcha-speaking Amerindians of Costa Rica and Panama.

Genetic variation of the Y chromosome in five Chibchan tribes (Bribri, Cabecar, Guaymi, Huetar, and Teribe) of Costa Rica and Panama was analyzed using six microsatellite loci (DYS19, DYS389A, DYS389B, DYS390, DYS391, and DYS393), the Y-chromosome-specific alphoid system (alphah), the Y-chromosome Alu polymorphism (YAP), and a specific pre-Columbian transition (C-->T) (M3 marker) in the DYS 199 locus that defines the Q-M3 haplogroup. Thirty-nine haplotypes were found, resulting in a haplotype diversity of 0.937.

Primary congenital glaucoma: a novel single-nucleotide deletion and varying phenotypic expression for the 1,546-1,555dup mutation in the GLC3A (CYP1B1) gene in 2 families of different ethnic origin.

Purpose: To present new molecular genetic data on primary congenital glaucoma from 2 families, 1 isolated case and 3 familial cases due to mutations in the cytochrome P-450 1B1 (CYP1B1) gene.

Methods: All diagnoses were made by slit-lamp biomicroscopy, gonioscopy, cornea and optic disk measurements, ultrasound-biometry, and automated static threshold perimetry where possible. Mutation screening was performed by direct sequence analysis of DNA extracted from peripheral blood of the patients and their relatives.

Novel mutations in the MYOC/GLC1A gene in a large group of glaucoma patients.

Mutations at the myocilin (MYOC) gene within the GLC1A locus have been revealed in 2-4% of patients suffering primary open angle glaucoma (POAG) worldwide. In our ongoing glaucoma study six hundred eighty two persons have been screened for MYOC mutations. The first group consisted of 453 patients from a long-term clinical study diagnosed either with juvenile OAG (JOAG), POAG, ocular hypertension (OHT) or normal tension glaucoma (NTG) plus 22 cases of secondary glaucoma.