ISSN:
1432-1432
Keywords:
Homologous mammalian genes
;
Compositional patterns
;
Synonymous positions
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract All 69 homologous coding sequences that are currently available in four mammalian orders were aligned and the synonymous (ie., third) positions of quartet (fourfold degenerate) codons were divided into three classes (that will be called conserved, intermediate, and variable), according to whether they show no change, one change, and more than one change, respectively. The three classes were analyzed in their compositional patterns. In the majority of GC-rich genes, the three classes of positions (but especially conserved positions) exhibited significantly different base compositions compared to expectations based on a “random” substitution process from the “ancestral” (consensus) sequence to the present-day (actual) sequences. Significant differences were rare in GC-poor genes. An analysis of the present results indicates that natural selection plays a role in the synonymous nucleotide substitution process, especially in GC-rich genes which represent the vast majority of mammalian genes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00163234
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