RESUMO
Milk is a primary protein source that has always played a role in mammalian health. Despite the intensification of research projects on dromedary and the knowledge of the genetic diversity at the casein loci, the genetic structure of the Tunisian camel population still needs exploration. This study sought to determine the genetic diversity of 3 casein gene variants in 5 Tunisian camel ecotypes: c.150G>T at CSN1S1 (αS1-casein), g.2126A>G at CSN2 (ß-casein), and g.1029T>C at CSN3 (κ-casein). The obtained results were compared with data published on Sudanese and Nigerian camels to establish the level of differentiation within and between populations. A total of 159 blood samples were collected from 5 Tunisian camel ecotypes and the extracted DNA was genotyped by PCR-RFLP. A streamlined genotyping protocol was also developed for CSN3. Results indicated that allele T was quite rare (0.06) at CSN1S1 for all ecotypes. Minor allele frequency was found for G (0.462) in CSN2 except for Ardhaoui Medenine ecotype who deviated from the average CSN2 allele frequency of the total population. Allele C showed minor allele frequency of 0.384 in CSN3. Among the Tunisian population, GAT (0.343) was the most represented haplotype in all ecotypes except for Ardhaoui Medenine, where GGC (0.322) was the most frequent one. Significant differences in heterozygosity and local inbreeding were observed across the Tunisian, Sudanese, and Nigerian populations, although the global fixation index indicated that only 2.2% of the genetic variance is related to ecotype differences. Instead, phylogenetic analysis revealed a closer link between the Tunisian and Sudanese populations through a clade subdivision with 3 main branches among the ecotypes. This study represents the first attempt to understand casein gene variability in Tunisian camels; with further study, milk traits and genetic differentiation among populations can be associated with the history of camel domestication.
Assuntos
Camelus , Caseínas , Animais , Camelus/genética , Caseínas/análise , Caseínas/genética , Leite/química , Nigéria , FilogeniaRESUMO
The Erdheim Chester disease is a rare form of non Langerhans cell histiocytosis. Its rarity and its unspecific clinical presentation, make that its diagnosis is often delayed. We report the case of a 50 years old female who has an Erdheim Chester disease, revealed by a central diabetes insipidus with thickening of the pituitary stalk, with associated gonadotropin deficiency. The Erdheim Chester disease was suspected because of the association with other evocative systemic lesions: eyelid xanthelasmas and bone lesions in metaphyseal-diaphyseal region of the upper and lower ends of both femurs and tibias on bone scan. Confirmation of the diagnosis was initially difficult and delayed, with initially inconclusive cutaneous and bone biopsies. It is the histological re-reading with immunohistochemical study of the bone biopsies which allowed the diagnosis by showing histiocytes positive for the CD68 and negative for the CD1a and the protein S100. The diagnosis was made with a delay of 3 years. In conclusion, although rare, Erdheim Chester disease should be suspected in front of a set of clinical and radiological arguments. Diagnostic confirmation is based on histological and especially immunohistochemical studies.
La maladie d'Erdheim Chester est une forme rare d'histiocytose non langerhansienne. Par sa rareté et son tableau clinique peu spécifique, son diagnostic est souvent retardé. Nous rapportons le cas d'une patiente âgée de 50 ans ayant une maladie d'Erdheim Chester révélée par un diabète insipide central avec épaississement de la tige pituitaire à l'IRM cérébrale et insuffisance gonadotrope associée. Cette maladie a été suspectée devant l'association d'autres atteintes systémiques évocatrices : des lésions cutanées à type de xanthélasmas sus-palpébraux de couleur jaune-orange et une atteinte osseuse au niveau métaphyso-diaphysaire des extrémités supérieures et inférieures des deux fémurs et tibias objectivée à la scintigraphie osseuse. La confirmation du diagnostic était initialement difficile et retardée, avec des biopsies cutanée et osseuse initialement non concluantes. C'est la relecture histologique avec étude immuno-histochimique des biopsies osseuses qui ont permis le diagnostic en montrant des histiocytes positifs pour le CD68 et négatifs pour le CD1a et la protéine S100. Le diagnostic positif a été posé avec un retard de 3 ans par rapport à la première consultation. En conclusion, bien que rare, la maladie d'Erdheim Chester devrait être suspectée devant un faisceau d'arguments cliniques et radiologiques. La confirmation diagnostique repose sur l'étude histologique et, surtout, immuno-histochimique.
