Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 2 de 2
Filter
Add filters








Language
Year range
1.
J Biosci ; 2008 Dec; 33(5): 761-70
Article in English | IMSEAR | ID: sea-111113

ABSTRACT

A recent phylogenetic study of langurs and leaf monkeys of South Asia suggested a reticulate evolution of capped and golden leaf monkeys through ancient hybridization between Semnopithecus and Trachypithecus .To test this hybridization scenario, I analysed nuclear copies of the mitochondrial cytochrome b gene (numts) from capped,golden and Phayre's leaf monkeys. These numts were aligned with mitochondrial cytochrome b sequences of various species belonging to the genera Semnopithecus and Trachypithecus .In the phylogenetic tree derived from this alignment,the numts fell into three distinct clades (A,B and C) suggesting three independent integration events.Clade A was basal to Semnopithecus, and clades B and C were basal to Trachypithecus. Among the numts in clades A and C were sequences derived from species not represented in their respective sister mitochondrial groups.This unusual placement of certain numts is taken as additional support for the hybridization scenario. Based on the molecular dating of these integration events,hybridization is estimated to have occurred around 7.1 to 3.4 million years ago.Capped and golden leaf monkeys might have to be assigned to a new genus to reconcile their unique evolutionary history. Additionally, northeast India appears to be a 'hot spot' for lineages that might have evolved through reticulate evolution.


Subject(s)
Amino Acid Sequence , Animals , Colobinae/genetics , Cytochromes b/chemistry , Evolution, Molecular , Hybridization, Genetic , Mitochondria/enzymology , Molecular Sequence Data , Phylogeny
2.
Mem. Inst. Oswaldo Cruz ; 103(1): 106-108, Feb. 2008. ilus, tab
Article in English | LILACS | ID: lil-478884

ABSTRACT

Paleoparasitological studies using microscopy showed that Ascarisand Trichuris trichiura are the human intestinal parasites most found in archaeological sites. However, in pre-Columbian South American archaeological sites, Ascaris is rare. In this work we standardized a molecular methodology for Ascaris diagnosis directly from ancient DNA retrieved from coprolites. Using cythochrome b gene (142 bp) target, ancient DNA sequences were retrieved from South American samples, negative by microscopy. Moreover, the methodology applied was sensitive enough to detect ancient DNA extracted from 30 Ascaris eggs from an European coprolite. These results revealed a new scenery for the paleodistribution of Ascaris in South America.


Subject(s)
Animals , History, Ancient , Humans , Ascariasis , Ascaris/genetics , Cytochromes b/genetics , DNA, Helminth/isolation & purification , Feces/parasitology , Paleopathology/methods , Ascariasis/diagnosis , Ascariasis/history , Ascaris/isolation & purification , Cytochromes b/chemistry , DNA, Helminth/chemistry , DNA, Helminth/genetics , Polymerase Chain Reaction , Sensitivity and Specificity , Sequence Analysis, DNA , South America
SELECTION OF CITATIONS
SEARCH DETAIL