| 摘要: | 應用分子遺傳資訊能提高選拔準確性，加速家畜性能的遺傳改進。單核苷酸多型性 (Single nucleotide polymorphism, SNP) 意指 DNA 序列中單一鹼基對的變異。本報告針對豬隻生產性狀候選基因 MC4R、HFABP、MSTN、CAST 及 POU1F1分析各基因型對豬隻生長、屠體、肉質及食用品質性狀的影響；同時發展微流道晶片辨識 SNP 多型性技術。試驗豬隻選自臺灣種豬場純種藍瑞斯、約克夏、杜洛克閹公豬與女豬共146頭，豬隻在場內飼養達檢定結束體重109.71 kg (SD = 13.76)，運送至台灣農畜產工業股份有限公司進行屠體測定，並取第九肋至最後肋的里肌肉進行肉質性狀分析；同時萃取 DNA，針對生產性狀候選基因分型，並利用不同解鏈溫度與動態對偶基因特異性雜交技術 (DASH) 發展 SNP 微流道晶片。所有資料以 SAS 軟體的 GLM 程序進行分析，統計模式以場別、品種、性別及基因型作為固定效應，並以屠前體重為共變量。分析發現杜洛克的肌內脂肪含量高於約克夏 (2.28 vs. 1.27 %, P < 0.05)，而性別則是以閹公豬較女豬高 (2.02 vs. 1.44 %, P < 0.05)。生長性狀中 CAST 基因 AA 與 AB 型較 BB 型早達到110 kg 體重 (193.03, 203.98 vs. 214.72 d, P < 0.05)。五個基因多型性皆與屠體、肉質及食用品質有關，MSTN (435/447) GAGA 型的瘦肉率高於 GGAA 型 (58.47 vs. 57.26 %, P < 0.05)，POU1F1 中 BB 型的脂肪率較 AB, AA 型低 (3.47 vs. 4.57, 4.79 %, P < 0.05)。主觀評分中 HFABP 基因 hh 型的大理石紋評分較 HH 型佳 (2.62 vs. 2.01, P < 0.05)，CAST 基因影響較多的食用品質性狀，多汁性、風味及異味評分結果，CAST/MspI 的 CC 與 CAST/RsaI的 EE 型分別較 DD 與 EF 型佳 (P < 0.05)。在 SNP 微流道晶片發展，本試驗已檢測 MC4R, HFABP/MspI, HFABP/HaeIII 及 MSTN g.435分型之解鏈溫度，且辨識分型檢測正確率100 %。本研究評估五個候選基因作為遺傳標記輔助選拔生產性狀之功能，並應用微流道晶片發展快速與便捷的分型技術，未來可建構遺傳評估方法，應用於產業現場，加速臺灣豬群生產性狀的遺傳改進。
Use of molecular genetic information can improve the selection accuracy and therefore accelerate genetic improvement of livestock performance. Single nucleotide polymorphism (SNP) is defined as the variation of a single base pair in DNA sequence. The purposes of this study were to analyzed the association between candidate genes MC4R, HFABP, MSTN, CAST and POU1F1 and growth, carcass, meat quality and eating quality traits in pigs. The microfluidic chip technology to detect SNPs was also developed. Barrows and gilts of 146 Landrace, Yorkshire and Duroc breeds were used in this study. All animals were kept in the commercial farms until reach the off test weight 109.71 kg (SD=13.76), and then transported to a commercial slaughter house for carcass measurement. Sections of the 9th rib to the last rib muscle were used for meat quality analysis. Tissue of ear sample were collected for DNA extraction, the candidate genes for production traits were genotypes, and SNP microfluidic chip was developed using melting curve analysis and dynamic allele-specific hybridization (DASH). All data were analyzed using GLM procedure of SAS with the model includes fixed effects of farm, breed, sex and genotypes. Preslaughter weight was used as a covariate in the model. Results of the analysis showed that loin of the intramuscular fat content of Duroc was higher than those of Yorkshire (2.28 vs. 1.27 %, P < 0.05), and barrows was higher than gilts (2.02 vs. 1.44 %, P < 0.05). For growth traits, pigs with CAST genotypes of AA, AB were reached 110 kg body weight faster than those of BB genotypes (193.03, 203.98 vs. 214.72 d, P < 0.05). Polymorphisms of these five genes were all related to carcass, meat quality and eating quality traits. Carcasses with MSTN (435/447) GAGA had higher lean percentage than those of GGAA (58.47 vs. 57.26 %, P < 0.05), and POU1F1 had lower fat percentage than those of AB, AA (3.47 vs. 4.57, 4.79 %, P <0.05). For the subjective score, loins with hh genotype in HFABP showed higher marbling score than HH loins (2.62 vs. 2.01, P < 0.05). CAST gene had a big impact on eating quality traits, include juiciness, flavor and off flavor, loins with the CC of CAST/MspI and the EE of CAST/RsaI expressed higher scores than those of the DD and EF (P < 0.05). As for the SNP microfluidic chip, the melting temperatures for MC4R, HFABP/MspI, HFABP/HaeIII and MSTN g.435 were detected, and the validation accuracy rate was 100 %. The study evaluated the five candidate genes as functional genetic markers to assist selection for production traits, and developed the fast and convenient genotyping technology of microfluidic chip. Method of genetic evaluation can be constructed and used in pig industry to accelerate the genetic improvement of production traits for pig population in Taiwan. |
