title: Patterns of nucleotide diversity and phenotypes of two domestication related genes (OsC1 and Wx) in indigenous rice varieties in Northeast India.
abstract: BACKGROUND
  During the domestication of crops, individual plants with traits desirable for human needs have been selected from their wild progenitors. Consequently, genetic and nucleotide diversity of genes associated with these selected traits in crop plants are expected to be lower than their wild progenitors. In the present study, we surveyed the pattern of nucleotide diversity of two selected trait specific genes, Wx and OsC1, which regulate amylose content and apiculus coloration respectively in cultivated rice varieties. The analyzed samples were collected from a wide geographic area in Northeast (NE) India, and included contrasting phenotypes considered to be associated with selected genes, namely glutinous and nonglutinous grains and colored and colorless apiculus.
  
  
  RESULTS
  No statistically significant selection signatures were detected in both Wx and OsC1gene sequences. However, low level of selection that varied across the length of each gene was evident. The glutinous type varieties showed higher levels of nucleotide diversity at the Wx locus (πtot = 0.0053) than nonglutinous type varieties (πtot = 0.0043). The OsC1 gene revealed low levels of selection among the colorless apiculus varieties with lower nucleotide diversity (πtot = 0.0010) than in the colored apiculus varieties (πtot = 0.0023).
  
  
  CONCLUSIONS
  The results revealed that functional mutations at Wx and OsC1genes considered to be associated with specific phenotypes do not necessarily correspond to the phenotypes in indigenous rice varieties in NE India. This suggests that other than previously reported genomic regions may also be involved in determination of these phenotypes.
authors.affiliation: Forest and Evolutionary Genomics Laboratory and Centre for Structural and Functional Genomics, Biology Department, Concordia University Montréal, 7141 Sherbrooke St, West, Montréal, Quebec H4B 1R6, Canada. baharul.choudhury@concordia.ca.
authors.forename: Baharul Islam
authors.initials: BI
authors.lastname: Choudhury
authors.forename: Mohammed Latif
authors.initials: ML
authors.lastname: Khan
authors.forename: Selvadurai
authors.initials: S
authors.lastname: Dayanandan
mesh_terms: D018744:DNA, Plant / Q000235:genetics; D017343:Genes, Plant; D006239:Haplotypes; D054643:INDEL Mutation; D007194:India; D018895:Microsatellite Repeats; D008969:Molecular Sequence Data; D009154:Mutation; D009711:Nucleotides / Q000235:genetics; D012275:Oryza / Q000235:genetics*; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D019655:Quantitative Trait, Heritable; D017422:Sequence Analysis, DNA
chemical_list: D018744:DNA, Plant; D009711:Nucleotides