Favia G, della Torre A, Bagayoko M, Lanfrancotti A, Sagnon N, Touré Y T, Coluzzi M
Istituto di Parassitologia, Fondazione Pasteur - Cenci Bolognetti, Università La Sapienza, Rome, Italy.
Insect Mol Biol. 1997 Nov;6(4):377-83. doi: 10.1046/j.1365-2583.1997.00189.x.
Three chromosomal forms of Anopheles gambiae s.s., designated as Bamako, Mopti and Savanna, were studied for diagnostic PCR assays based on the analysis of the X-linked ribosomal DNA (rDNA). The study was performed on a 1.3 kb fragment containing part of the 28S coding region and part of the intergenic spacer region. The amplified material was cut with fourteen restriction enzymes to detect Restriction Fragment Length Polymorphisms (RFLPs). The enzymes Tru9I and HhaI produced patterns of DNA bands which differentiated Mopti from Savanna and Bamako; moreover, a distinct 'hybrid' pattern was recognized in the F1 female progeny from the cross of Mopti with either one of the other two chromosomal forms. The diagnostic significance of the PCR-RFLP assay was verified on 203 karyotyped females from field samples collected in two villages in Mali and one village in Burkina Faso. Agreement was observed between the chromosomal and the molecular identifications. No 'hybrid' molecular patterns were detected even among carriers of rare heterokaryotypes hypothetically produced by crosses between Mopti and Savanna. The results confirm previous observations indicating barriers to gene flow within An. gambiae s.s. and supporting the specific status of the taxonomic units proposed on cytogenetic ground.
基于对X连锁核糖体DNA（rDNA）的分析，对冈比亚按蚊指名亚种的三种染色体形式（即巴马科型、莫普提型和稀树草原型）进行了诊断性PCR检测。该研究针对一个1.3 kb的片段展开，该片段包含部分28S编码区和部分基因间隔区。扩增产物用14种限制性内切酶切割，以检测限制性片段长度多态性（RFLP）。Tru9I和HhaI这两种酶产生的DNA条带模式可区分莫普提型与稀树草原型和巴马科型；此外，在莫普提型与其他两种染色体形式之一杂交产生的F1雌性后代中识别出一种独特的“杂交”模式。在从马里的两个村庄和布基纳法索的一个村庄采集的野外样本中的203只经核型分析的雌性样本上验证了PCR-RFLP检测的诊断意义。在染色体鉴定和分子鉴定之间观察到了一致性。即使在假设由莫普提型和稀树草原型杂交产生的罕见异核体携带者中，也未检测到“杂交”分子模式。结果证实了先前的观察结果，表明冈比亚按蚊指名亚种内存在基因流动障碍，并支持基于细胞遗传学提出的分类单元的特定地位。
