Mitochondrial DNA polymorphism analyzed by restriction endonucleases in two sardinian populations

Polymorphism of mitochondrial DNA by means of restriction endonucleases analysis has been studied in two sardinian isolates, formerly subjected to different selective pressure due to malaria. The mitochondrial DNA haplotype frequencies differ significantly between the two villages. An evaluation of variability through Wahlund variance analysis rules out selective factors and suggests drift

Polimorfismo genetico mitocondriale in popolazioni sarde esposte a differente pressione selettiva malarica

Studio dei polimorfismi del DNA mitocondriale analizzati mediante enzimi di restrizione, in relazione alla suscettibilit\ue0 all'infezione malarica. Sono state individuate numerose differenze statisticamente significative tra gli individui provenienti da isolati sardi di montagna (non soggetti ad infezione malarica) rispetto a quelli di pianura (soggetti all'infezione. Tuttavia l'analisi della varianza secondo Wahlund ha dimostrato che le differenze sono dipendenti da deriva genetica

Mitochondrial DNA polymorphism in four Sardinian villages

Polymorphism of mitochondrial DNA has been studied in two highland (Desulo, Tonara) and in two lowland (Galtelli, Orosei) Sardinian isolates, formerly subjected to different selective pressure due to malaria, and in 103 individuals from Northern Italy (Bergamo area), where malaria never appeared to be endemic. Two mitochondrial restriction endonuclease patterns (morphs) never described before have been found, one in the Bergamo and Orosei samples, and the other one only in Orosei. Four new mitochondrial types (mitotypes) due to different combinations of morphs have been identified; two of them have been found only in Sardinia, but with such a low frequency that they cannot be defined as typical Sardinian mitotypes. One mitotype (BamHI-morph 3, MspI-morph 4, AvaII-morph 9 and HaeII-morph 1) showed a significantly higher frequency in the highland rather than in the lowland Sardinian villages or in the Bergamo area. Since this mitotype has been found at a relatively high frequency in Central and Southern Italy, while it has been reported to be rare in Caucasians of Central European origin and absent in other ethnic groups (Africans, Chinese, Japanese and Israeli Jews), we suggest it may represent an ancient Mediterranean type. The analysis of these data suggests that drift or other evolutive forces different from malaria might be the major cause of mitochondrial DNA variation in Sardinia

European Commission, Standards, Measurement and Testing Programme. Project SMT4-CT95-7501: intercomparison of impulse charge measurement

Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome / CNR - Consiglio Nazionale delle RichercheSIGLEITItal