Expressed sequence tag–simple sequence repeats isolated from Shorea leprosula and their transferability to 36 species within the Dipterocarpaceae


Kevin Kit Siong Ng, Fax: 603 62804614; E-mail:


Simple sequence repeats (SSRs) derived from expressed sequence tags (ESTs) are valuable markers because they represent transcribed regions and often transferable to related taxa. Here, we report the development and characterization of EST–SSRs from Shorea leprosula. Fifty-four sequences containing SSRs were identified in 2003 unigenes assembled from 3159 ESTs. Twenty-four EST–SSRs were developed, of which four gave multiple amplifications, five were found to be monomorphic and 15 showed polymorphism, with allele numbers ranging from two to 17 in a single Pasoh Forest Reserve population of 24 individuals. The observed and expected heterozygosities ranged from 0.05 to 0.91 and from 0.16 to 0.93, respectively. Cross-species transferability of the 15 loci to 36 species within Dipterocarpaceae revealed between four and 14 loci that gave positive amplification and 10 loci were found to be transferable to more than 15 species.