Potato Journal
  • Year: 2004
  • Volume: 31
  • Issue: 3 and 4

Occurrence of simple sequence repeats in potato ESTs is not random: An in silico study on distribution and length of simple sequence repeats

  • Author:
  • Atul Grover1, Prakash C. Sharma2
  • Total Page Count: 8
  • Page Number: 95 to 102

1Department of Biotechnology, Ch. Charan Singh University, Meerut, 250 005, Uttar Pradesh, India.

2School of Biotechnology, GGS Indraprastha University, Delhi, 110 006, India.

Abstract

More than 29,000 potato ESTs were analyzed for the occurrence of mono-, di-, tri- and tetranucleotide repeats. 173 complex and 1291 simple SSRs with minimum size of 12 base pairs were located in 1217 ESTs. Trinucleotide repeats represent 66% of these. More than 25% of all the repeats belong to (AAG)n class. Dinucleotide and tetranucleotide repeats have relative frequencies of 15% and 8%, respectively. Dinucleotide stretches were found to be longer than others. Point mutations have been recognized to have some role in evolution and length determination of a repeat, but other factors also account for the abundance and distribution of SSRs.