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Fishery Bulletin 91(4). 1993 



154 

 134 



Lane 



Figure 1 



Restriction profiles of cytochrome b lAl and 12S rRNA iBi 

 gene fragments amplified by PCR. IA) lanes 1 and 14 (size 

 standard), 2 (blank), 3 and 4 (La and Ra digested by Alu Ii, 5 

 and 6 (Lap and Lv digested by Cfo I), 7 and 8 (La and Ra 

 digested by Dde I), 9 and 10 (Ra and Ls digested by Hae III), 

 11 and 12 (Lap and Ra digested by Hm fh, and 13 (La no 

 digestion); (B) lanes 1 and 14 (size standard), 2 (La no diges- 

 tion), 3 (La digested by Alu I), 4 (Lb digested by Cfo I), 5 (Ls 

 digested by Dde I), 6 (Lg digested by Hae III), 7 (Oc digested 

 by Hin fl), 8 iLs digested by Mbo I), 9 and 10 (Lg and La2 

 digested by Msp I), 11 and 12 (Lg and La digested by Tag I), 

 and 13 (blank). 



For the 355 bp cytochrome b fragment, four enzymes 

 (Mbo I, Msp I, Rsa I and Taq I) had no restriction sites 

 in any of the species. Dde I had restriction site(s) in all 

 species examined, without apparent size difference in 

 restricted fragments within and between species. Varia- 

 tion on the restricted fragment length within and be- 

 tween species was observed for four of the nine en- 

 zymes examined. Alu I appeared to have no restriction 

 sites in this fragment of all Lutjanus spp. and 0. 

 chrysurus (Oc), but two restriction sites producing three 

 fragments (170, 110 and 74 bp) were evident in R. 

 aurorubens (Ra). Cfo I, Hae III and Hin ft digestions 

 revealed polymorphism within species; L. griseus (Lg) 

 for all three enzymes, L. analis (La) for Cfo I and Hin 

 fl, L. eampechanus (Lc) for Hae III and Hin fl, and 0. 

 chrysurus (Oc) for Cfo I only. 



All nine enzymes had recognition site(s) in the 450 

 bp 12S rRNA fragment of at least one species. No 

 length variation of the restricted fragments between 

 species was observed for Cfo I and Hae III digestions. 

 Taq I digestion produced 230 and 170 bp fragments in 

 L. griseus (Lg), while 280 and 170 bp fragments were 

 observed in the other species. Intraspecific polymor- 

 phism was observed for the other six enzymes; Alu I 

 (for Lc, Ley, Lg, and Lj), Dde I (for Lc, Ley, and Lg), 

 Hin fl (for La, Lap, Ley, and Lj), Mbo I (for La, Lc, and 

 Lj), Msp I (for La, Ley, and Lj), and Rsa I (for Lc, Ley, 

 and Lj). 



Data of restriction fragment patterns were summa- 

 rized for haplotype analysis for species discrimination 

 (Table 4). Straightforward diagnostic restriction pro- 

 files were observed in the 12S rRNA fragment of L. 

 griseus (Lg) digested by Taq I and in the cytochrome b 

 fragment of/?, aurorubens (Ra) digested by Alu I, with- 

 out RFLP within species. Haplotype analysis on cyto- 

 chrome b fragment separated L. cyanopterus (Ley) and 

 L. vivanus (Lv), and that on 12S rRNA gene fragment 

 separated L. eampechanus (Lc). L. apodus (Lap), L. 

 buccanella (Lb) and L. synagris (Ls) were deseriminated 

 by haplotype analysis on both fragments. In contrast, 

 identical haplotypes were found in five individuals of 

 L. analis (Lai, 5, 52-54), all of L. mahogony (Lml, 2, 

 M2) and in seven of O. chrysurus (Ocl-7), and in two 

 individuals of L. jocu (LjM2, M3) and in one of L. 

 purpureus (LpM2). One individual of L. analis (La2), 

 two of L. jocu (LjMl, M7), and one of O. chrysurus 

 (Oc50) had their own distinct haplotype. 



Mean percent nucleotide sequence divergence (p) 

 within species ranged from to 2.43 with an average 

 of 0.65. The nucleotide sequence divergence for those 

 between species within the genus Lutjanus ranged from 

 0.11 to 3.84 with an average of 1.69, for those between 



