Abstract: Abstract: Objective Analysis of 6 SNPs associated to nerve pattern related 4 genes in Labrador Ｒetrievers to provide a early-stage molecular genetic index for nerve pattern diagnostics． Method According to the behavior evaluation standards of China guide dog training center，the dogs belong to typical nerve patterns ( quiet，active， and timid ( weak ) type，4 dogs each) were selected． The vein blood was sampled and the genomic DNA was isolated from blood cells． The PCＲ/sequencing and PCＲ-ＲFLP method were used to analyze the variants of 6 SNPs in nerve pattern related 4 genes: ( COMT ( G482A) ，MOAB ( T199C) ，ABCB1 ( A985T，T3442C，377 － 378 insC) ，GNB1L( 961 － 962 insG) ) ． Furthmore，the association between the SNP variants and nerve patterns was analyzed by Chi-square Test． Ｒesult G/A variants in COMT ( G482A) SNP locus in the proportion of timid dogs was significantly higher than that in the active and quiet dogs ( P = 0. 014; P = 0. 014) ，A/A variants in COMT ( G482A) SNP locus in the proportion of active dogs was significantly higher than that in the quiet and timid dogs ( P = 0. 025; P = 0. 025 ) ; T /C variants in MAOB ( T199C) SNP locus in the proportion of quiet dogs was significantly higher than that in the active and timid dogs ( P = 0. 025; P = 0. 025 ) ; T /A variants in ABCB1 ( A985T) SNP locus in the proportion of active dogs was significantly lower than that in the quiet and timid dogs ( P = 0. 014; P = 0. 014 ) ; T /C variants in ABCB1 ( T3442C) SNP locus in the proportion of timid dogs was significantly lower than that in the quiet and active dogs ( P = 0. 025; P = 0. 025) ; No ABCB1 ( 377 － 378 insC) and GNB1L ( 961 － 962 insG) SNP loci was found． Conclusion G/A and A/A variants in COMT ( G482A) 、T /C variants in MAOB ( T199C) 、T /A variants in ABCB1 ( A985T) and T /C variants in ABCB1 ( T3442C) are significantly associated to nerve patterns and might be used as a molecular genetic index for nerve pattern diagnostics in Labrador Ｒetrievers． However，further large sample analysis is required．

Key words: Labrador Ｒetrievers, nerve pattern, SNP, molecular genetic diagnostics

摘要： 摘要: 目的检测拉布拉多犬基因组DNA 中与神经类型密切相关的4 个基因中的6 个SNP 位点，以期为拉布拉多犬神经类型的早期鉴定提供分子遗传学鉴定指标。方法依据中国导盲犬大连培训基地成熟的导盲犬神经类型行为学评估标准，选取典型的安静、活泼、胆小型( 弱型) 三种神经类型的犬各4 只为研究对象，采取静脉血，提取血细胞的基因组DNA 样本，采用PCＲ/测序方法和PCＲ-ＲFLP 分析法对12 个样本4 个基因的6 个SNP 位点: COMT( G482A) 、MOAB( T199C) 、ABCB1( A985T、T3442C、377 － 378 insC) 、GNB1L( 961 － 962 insG) 进行变异型检测，并统 计分析SNP 位点的变异型与神经类型的关联度。结果COMT 基因G482A SNP 位点的G/A 型在胆小型犬中所占比例显著高于其在活泼型和安静型中所占比例( P = 0. 014; P = 0. 014) ，A/A 型在活泼型犬中所占比例显著高于安静型和胆小型中所占比例( P = 0. 025; P = 0. 025) ; MAOB 基因T199C SNP 位点的T/C 型在安静型犬中所占比例显著高于其在活泼和胆小型犬中所占比例( P = 0. 025; P = 0. 025) ; ABCB1 基因A985T SNP 位点的T/A 型在活泼型犬中所占比例显著低于其在安静和胆小犬中所占比例( P = 0. 014; P = 0. 014) ; ABCB1 基因T3442C SNP 位点的T/C型在胆小型犬中所占比例显著高于其在活泼和安静型犬中所占比例( P = 0. 025; P = 0. 025) ; ABCB1 基因的377 －378 insC 和GNB1L 基因的961 － 962 insG 均没有发现显著性差异( P ＞ 0. 05) 。结论COMT 基因G482A SNP 位点的G/A 型和A/A 型，MAOB 基因T199C SNP 位点的T/C 型，ABCB1 基因A985T SNP 位点的T/A 和ABCB1 基因T3442C SNP 位点的T/C 型与拉布拉多犬神经类型具有显著相关性，可做为拉布拉多犬神经类型早期鉴定的分子遗传诊断指标，但尚需大样本确认。

关键词: 拉布拉多犬, 神经类型, 单核苷酸多态性( SNP), 分子遗传学诊断