The F2 population containing 500 individuals was developed using two cultivated rice germplas-ms (Oryza sativa L.) , HTTAR005 as female parent from HTTAR and IRGC20509 as male parent from IRRI, and the ILP (intron length polymorphism) markers were employed to genotype the 117 individuals of the F2 population.
The DNA and cDNA sequences of chi46 were 1466bp and 1 350bp in length, respectively, which encoded 449 amino acid residues with molecular weight of 46.2kD and the isoelectric point of 5.38. The DNA sequence of chi46 was composed of 2 exons and 1 intron, the 2 exons were 528bp and 822bp in length respectively, and the intron length was 73bp.
The junction sequences of exons and introns accorded to the classical cut and assembly sequence GT/AG The length of 5 exons were 478bp , 1106bp, 290bp, 793 and 779bp respectively, and that of the 4 introns were 195bp, 156bp, 87bp and 88bp respectively.
The full length of Lac1 gene was 2338bp, with 10 introns and 11 exons. Introns ranged in size from 51 to 76bp, and its sequence complied with the rule of “5'-gt” and “ag-3'”.
Whether the length and nucleotide polymorphisms in the intron2 of crucian carp GHⅠ gene were associated with gene expression and gene regulation remained unsolved and required further investigations.
Deletion breakpoints were homogeneously distributed throughout the intron length, and no extensive homology was observed between the sequences adjacent to each breakpoint.