Volga German surnames and Alzheimer's disease in Argentina: an epidemiological perspective.

The N141I variant (PSEN1 gene) is associated with familial forms of early-onset Alzheimer's disease (AD) in descendants of Volga Germans, whose migration to Argentina is well documented. As a proxy for geographic origin, surnames can be a valuable tool in population studies. The 2015 Argentine Electoral Registry provided geographic data for 30,530,194 individuals, including 326,922 with Volga German surnames. Between 2005 and 2017, the Ministry of Health recorded 4,115,216 deaths, of which 17,226 were attributed to AD and related causes. The study used both diachronic and synchronic data to identify patterns of territorial distribution and co-spatiality, using Moran's I and generalised linear model statistics. The frequency of surnames of Volga German origin accounts for 43.53% of the variation in deaths from AD and three clusters of high non-random frequency were found. Almost 150 years later, people descending from the Volga migration remain highly concentrated and may have a different risk of developing AD. The identification of spatial patterns provides reliable guidance for medical research and highlights the importance of specific health policies for particular populations.

Chilean reference of length at birth.

BACKGROUND: To generate a reference of length at birth (LB) according to sex and gestational age (GA) of the Chilean population. METHODS: This cross-sectional observational study used public pooled Chilean newborn (NB) population data registered by the Civil Registry and Identification Service in Chile from 2000 to 2016. Multiple births, entries without information for LB, GA, and sex, and birth lengths <-4SD and > 4SD, were excluded. After applying the selection and randomization criteria, the final sample was made up of 5 010 963 NB (2 560 310 boys; 2 450 653 girls). Length at birth centiles by sex and GA (24-42 weeks) were calculated using the GAMLSS method and then compared with the INTERGROWTH-21st standard. RESULTS: Girls had a lower LB than boys. For most GA and in both sexes, the absolute and percentage differences of percentiles as compared with INTERGROWTH-21st were lower than 1 cm and 1%, respectively. CONCLUSIONS: We present a reference for LB by sex and GA in the Chilean population, developed following updated methodological criteria for neonatal anthropometry, which is acceptably consistent with the INTERGROWTH-21st standard. The reference we propose may be used in clinical and epidemiological studies to identify either Chilean individuals or populations, respectively, at higher risk of perinatal and infant adverse events related to LB.

Apolipoprotein E Polymorphisms in Andean Population of Jujuy, Argentina.

The pleiotropic nature of the apolipoprotein E (APOE) gene is associated with complex diseases in different populations. We analyzed APOE polymorphisms in 76 individuals from Jujuy - Argentina using NGS technology. The observed genotypes align with the expected Hardy-Weinberg equilibrium. APOE3 was the most common allele, followed by APOE4 and APOE2. The allele distribution pattern is consistent with findings in previously studied populations of Native Americans and Asians. The E4 allele's low frequency, always observed in a heterozygous state, raises questions regarding its relevance in explaining dementia and longevity associated with this marker in the Central Andes.

Birth Size and Maternal, Social, and Environmental Factors in the Province of Jujuy, Argentina.

INTRODUCTION: birth size is affected by diverse maternal, environmental, social, and economic factors. AIM: analyze the relationships between birth size-shown by the indicators small for gestational age (SGA) and large for gestational age (LGA)-and maternal, social, and environmental factors in the Argentine province of Jujuy, located in the Andean foothills. METHODS: data was obtained from 49,185 mother-newborn pairs recorded in the Jujuy Perinatal Information System (SIP) between 2009 and 2014, including the following: newborn and maternal weight, length/height, and body mass index (BMI); gestational age and maternal age; mother's educational level, nutritional status, marital status and birth interval; planned pregnancy; geographic-linguistic origin of surnames; altitudinal place of birth; and unsatisfied basic needs (UBN). The dataset was split into two groups, SGA and LGA, and compared with adequate for gestational age (AGA). Bivariate analysis (ANOVA) and general lineal modeling (GLM) with multinomial distribution were employed. RESULTS: for SGA newborns, risk factors were altitude (1.43 [1.12-1.82]), preterm birth (5.33 [4.17-6.82]), older maternal age (1.59 [1.24-2.05]), and primiparous mothers (1.88 [1.06-3.34]). For LGA newborns, the risk factors were female sex (2.72 [5.51-2.95]), overweight (1.33 [1.22-2.46]) and obesity (1.85 [1.66-2.07]). CONCLUSIONS: the distribution of birth size and the factors related to its variability in Jujuy are found to be strongly conditioned by provincial terrain and the clinal variation due to its Andean location.