臺灣黑山羊粒線體DNA D環區序列比較

本試驗旨在分析臺灣黑山羊花蓮品系（Hua）及恆春品系（KT）粒線體DNA（mitochondrial DNA，mtDNA）中D-loop（1,212 bp）序列之比對結果。結果顯示此兩群山羊D-loop序列中，腺嘌呤（A）＋胸腺嘧啶（T）之比例為60.2－60.4％，其DNA鹼基中呈現腺嘌呤與胸腺嘧啶總合較多的現象。臺灣黑山羊花蓮及恆春品系D-loop各具有10種及3種單套型（haplotype）。序列共有15處變異點，分別位於447、451、468、470、483、490、500、520、548、610、632、802、1005、1055及1141 bp。其中A/G轉換有7處，T/C轉換有8處。兩族群之單倍體基因多樣性指數（hd）、核苷酸多樣性指數（nucleotide diversity，π）及Tajima's D值，分別呈現高的hd值，低的π值及D＜0。推測族群可能過去曾遭遇數量大量減少後，再急遽的擴充群族數量。遺傳分化指數（Fst）為0.37715，基因流傳值（Nm）為0.41，顯示兩族群間交流程度低。推測可能是由於最初引種時，羊隻在台灣地理上之區隔與後續人為選育種計畫上之差異。

關鍵字

臺灣黑山羊；粒線體基因； D環區

並列摘要

Taiwan native black goats, which were raised at Hualien and Hengchung station, had a relative relationship at twenty years ago. The purpose of this study was to compare the differences of the D-loop gene (1,212 bp) in mitochondrial DNA between these two herds, which were named as Hua and KT breeds. The result showed the D-loop sequence of experimental goat was A-T rich. A+T content occupied 60.2-60.4％ of total content. There are ten and three haplotypes of D-loop in Hua and KT breeds, respectively. Fifteen polymorphic sites in the D-loop sequence were located at 447, 451, 468, 470, 483, 490, 500, 520, 548, 610, 632, 802, 1005, 1055 and 1141 bp respectively. Seven A/G and eight T/C transition pairs were founded. The value of the haplotype diversity (hd) was high. Meanwhile, the nucleotide diversity (π) was low and the Tajima's D was smaller than 0. The evidence verified that these two herds had a relative relationship in the past time. Furthermore, the data also inferred the possibilities of goat population change in the past two decades. It seems that these two herds might have incurred the huge population decline in the past and then rapidly increased herd population size recently. The estimates of Fst and Nm were 0.37715 and 0.41, respectively. Evidence showed that there was a low gene flow between these two groups. The low relative relationship between these two herds might come from the geography division of Taiwan and the man-made of breeding or selection programs.

並列關鍵字

Taiwan native black goat ； Mitochondrial DNA ； D-loop

主題瀏覽