en Genetics Genetics پژوهشي Orginal research papers <span style="FONT-FAMILY: "Times New Roman","serif" FONT-SIZE: 12pt mso-fareast-font-family: Calibri mso-bidi-language: FA mso-ansi-language: EN-US mso-fareast-language: EN-US">Sampling was done using 90 post larvae which were produced by reproduction of some broodstocks of <i>Fenneropenaeus indicus</i> in one day and reared in the same situation for 4 months. Samples were divided into 3 groups: high, medium and low growth (based on weight and length). Genomic DNA was extracted from muscle tissue using the phenol-chloroform method. The polymerase chain reaction (PCR) was carried out using 21 RAPD loci and PCR products were separated on 3% Agarose gel. From 21 loci studied, 12 produced polymorphic bands. The most polymorphic produced bands using OPAQ 9 and the least by OPAQ 7. Search for specific markers in <i>F. indicus </i>one specific band was observed in the low growth group using </span><span style="FONT-FAMILY: "Times New Roman","serif" FONT-SIZE: 11pt mso-fareast-font-family: Calibri mso-bidi-language: FA mso-ansi-language: EN-US mso-fareast-language: EN-US">OPAQ4.</span><span style="FONT-FAMILY: "Times New Roman","serif" FONT-SIZE: 12pt mso-fareast-font-family: Calibri mso-bidi-language: FA mso-ansi-language: EN-US mso-fareast-language: EN-US"> The highest genetic distance (0.457) was between the low growth group and the medium and the lowest (0.091) between high growth and medium groups, therefore the highest genetic identity (0.912) was between high growth and medium groups and the lowest (0.633) between low growth group and the medium. Neighbor-joining resulted in two groups, the first including high and medium growth groups and the second low growth group. It appears that low growth group depended on separated population. Considering the mean weight of F₁ (mean weight of 90 specimens) (16.25±1.5 g), parental generation mean weight of 15 ±1.2 and mean weight of parent 31.6 g, response to selection (R) and heritability for growth in this species were estimated<font size="3"><font face="Times New Roman"><span style="mso-spacerun: yes">  </span>to be 1.2±0.2 and 0.07±0.01 respectively.</font></font></span> Feneropenaeus indicus, RAPD marker, Heritability, Growth, Iranian Fisheries 123 134 http://jifro.ir/browse.php?a_code=A-10-1-66&slc_lang=en&sid=1 S. Rezvani Gilkolaei rezvani@ifro.ir 10031947532846001104 10031947532846001104 Yes R. Safari 10031947532846001105 10031947532846001105 No F. Laloei 10031947532846001106 10031947532846001106 No J. Taqavi 10031947532846001107 10031947532846001107 No A. Matinfar 10031947532846001108 10031947532846001108 No