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Publications (2)0.96 Total impact

  • I Salces, E Rebato, C Susanne, R C Hauspie, R Saha, J R Fernández-López, P Dasgupta
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    ABSTRACT: The aim of the present study was to examine the heritability of 11 traits in a mixed-longitudinal sample of Indian siblings, and to determine whether heritability estimates vary during the growth period and whether they are influenced by sex. The sample consisted of 245 brothers and 213 sisters from 138 nuclear families living in a semi-urban area in Kolkata, India. The age ranged between 5 and 19 years. The traits were standardised for age and sex using standard deviation scores (SDS) produced by the LMS method (Cole, T.J., 1988. Fitting smoothed centile curves to reference data. J. R. Stat. Soc. A 151, 385-418). The standard deviation scores were analysed by PCA. The two factors with eigenvalues above 1 explained 77.3% of the variance; they showed a high level of pleiotropism present among the studied traits and represented body lengths (PC1) and body weight and breadths (PC2). The heritability between all types of siblings (irrespective of sex) for the PC1 and PC2 was estimated. The heritability between various pairs of siblings showed variations along the whole ontogenetic period studied. During the childhood and pre-pubertal period, heritability between brothers, brother-sister pairs and any sibling pairs was mostly constant, with small and non-significant variations. All the pairs showed the lowest degree of heritability during puberty for PC1 but not for PC2, with significant changes of heritability estimates between adolescence and adulthood, in most of the analysed sibling pairs and in both PC factors. The highest heritability was generally observed at the end of the examined growth period in all pairs. A significant effect of sex on heritability was only detected for PC2 at 11 years of age.
    Homo: internationale Zeitschrift fur die vergleichende Forschung am Menschen 07/2009; 60(4):373-88. · 0.96 Impact Factor
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    Itziar Salces, Esther REBATO OCHOA, Liuba Bilbao, Juan Ramón Fernández-López
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    ABSTRACT: During the years 1988-1998, three cross-sectional studies of growth in schoolchildren of different cities of the Biscay province, aged 4 to 18 years, were performed. In this preliminary study, mean stature and weight of the three samples were compared in the age-range 8 to 18 years and no significant differences were found in both sexes. Since secular trend was absent, these data can be considered as originating from a global sample, and we propose to combine it into a single sample, representing the whole province, for percentile estimation and fitting through appropriate mathematical models, with the aim of obtaining the reference charts of height and weight in this population. Durant la période 1988-1998, nous avons réalisé trois études transversales de croissance, chez des écoliers de différentes localités de la province de Biscaye, avec des âges compris entre 4 et 18 ans. Dans cette étude préliminaire, nous avons comparé les tailles et poids moyens des trois échantillons pour les groupes d'âge de 8 à 18 ans et nous n'avons pas trouvé de différences notables pour aucun des sexes. En raison de l'absence d'évolution séculaire, ces données peuvent donc être considérées comme provenant d'un échantillon global, pour lequel nous proposons son unification en un échantillon représentatif de la province, et ceci aux fins de l¿estimation de percentiles et de l'ajustement à des modèles mathématiques appropriés, afin d¿obtenir des courbes de référence pour la taille et le poids de cette population.
    Antropo, ISSN 1578-2603, Vol. 11, 2006 (Ejemplar dedicado a: XXVIIº Colloque du Groupement des Anthropologistes de Langue Française (GALF) : Anthropobiologie, évolution et histoire des peuplements), pags. 15-24.