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Myanmar indigenous chickens play important roles in food, entertainment, and farm business for the people of Myanmar. In this study, complete mitochondrial D-loop sequences (1232 bp) were analyzed using 176 chickens, including three indigenous breeds, two fighting cock populations, and three indigenous populations to elucidate genetic diversity and accomplish a phylogenetic analysis of Myanmar indigenous chickens. The average haplotype and nucleotide diversities were 0.948 ± 0.009 and 0.00814 ± 0.00024, respectively, exhibiting high genetic diversity of Myanmar indigenous chickens. Sixty-four haplotypes were classified as seven haplogroups, with the majority being haplogroup F. The breeds and populations except Inbinwa had multiple maternal haplogroups, suggesting that they experienced no recent purifying selection and bottleneck events. All breeds and populations examined shared haplogroup F. When 232 sequences belonging to haplogroup F (79 from Myanmar and 153 deposited sequences from other Asian countries/region) were analyzed together, the highest genetic diversity was observed in Myanmar indigenous chickens. Furthermore, Myanmar indigenous chickens and red junglefowls were observed in the center of the star-like median-joining network of 37 F-haplotypes, suggesting that Myanmar is one of the origins of haplogroup F. These findings revealed the unique genetic characteristic of Myanmar indigenous chickens as important genetic resources.

Defective appearances, including white spotting (WS), tongue defect (TD), and nipple defect (ND), in Japanese Black cattle potentially lead to economic losses to farmers in Japan. We estimated genetic parameters of defective appearances using 553,433 records of Japanese Black heifer calves housed in the Kagoshima Prefecture. Variance and covariance were estimated using the Gibbs sampling algorithm. The estimated heritability ranged from 0.29 for TD to 0.76 for WS. Percent breeding value (%BV) estimates indicated high variation in WS and ND among sires, reflecting higher heritability. Furthermore, there was a positive linear relationship between the %BV estimate of a sire and the mean incidence rate of each defect in his female offsprings. TD was positively associated with other defects. Therefore, genetic factors strongly affect the incidence of defective appearances in Japanese Black cattle.

Local cattle breeds are popular in Myanmar because they make excellent draught animals, so it is of fundamental importance that their genetic diversities and population structures are elucidated for breeding and conservation purposes. In this study, we characterized the genetic diversities and population structures of four popular Myanmar local cattle breeds and five native cattle populations from neighboring countries (Bangladesh, Laos, Cambodia, and Vietnam) using the GGP Bovine 50K array. The mean observed and expected heterozygosity estimates using pruned datasets ranged from 0.317 and 0.322, respectively, in Cambodia to 0.448 and 0.421, respectively, in Vietnam South. The four Myanmar local breeds exhibited similar levels of genetic diversity. However, AMOVA revealed significant genetic differentiation among the nine populations (p < 0.00001), and Neighbor-Net analysis showed that Shan Ngwar Pu was distinct from the other Myanmar local breeds. Furthermore, PCA and population structure analyses revealed that the native cattle from neighboring countries genetically influenced the Myanmar local breeds to some extent and that the genetic origins could also be observed in the local breeds. These findings highlight the importance of Myanmar local breeds as genetic resources and provide useful information for the future development of breeding strategies and conservation management plans.

Cattle exhibit a range of carcass defects, including blood splash (BLS), intramuscular edema (INE), muscle steatosis (MUS), bruising (BR), trim loss (TRL) and others (OTH). These defects lower the carcass value and can result in significant economic loss to producers. We estimated the incidence, relationship with inbreeding coefficients and genetic parameters of carcass defects in Japanese Black cattle using 561 619 carcass records from Kagoshima, Japan during April 1988 through March 2011. The defect incidence ranged from 0.22% for TRL to 5.73% for BR. The incidence of MUS and BR increased from 1.21% to 6.57% and from 1.06% to 9.31%, respectively. The incidence of INE peaked at 7.44% in 1999 and decreased thereafter. We observed a positive linear relationship between the defect incidence and the inbreeding coefficients in MUS, BR and TRL (P < 0.01). The heritabilities estimated by univariate animal model with Gibbs sampling for BLS, INE, MUS, BR and TRL were 0.24, 0.06, 0.18, 0.05 and 0.02, respectively. The contribution of farm variance to phenotypic variance was negligible (0.01 to 0.04). Significant genetic correlations of TRL were estimated with MUS (0.63) and BR (0.63). Our results suggest that genetic factors contribute to the incidence of BLS and MUS.

The genetic diversity of native chicken populations from Myanmar, Thailand, and Laos was examined by using 102 insertion and/or deletion (indels) markers. Most of the indels loci were polymorphic (71% to 96%), and the genetic variability was similar in all populations. The average observed heterozygosities (H O ) and expected heterozygosities (H E ) ranged from 0.205 to 0.263 and 0.239 to 0.381, respectively. The coefficients of genetic differentiation (Gst) for all cumulated populations was 0.125, and the Thai native chickens showed higher Gst (0.088) than Myanmar (0.041) and Laotian (0.024) populations. The pairwise Fst distances ranged from 0.144 to 0.308 among populations. A neighbor-joining (NJ) tree, using Nei's genetic distance, revealed that Thai and Laotian native chicken populations were genetically close, while Myanmar native chickens were distant from the others. The native chickens from these three countries were thought to be descended from three different origins (K = 3) from STRUCTURE analysis. Genetic admixture was observed in Thai and Laotian native chickens, while admixture was absent in Myanmar native chickens.

Here, we studied the genetic diversity of native fowls in Laos by analyzing a mitochondrial DNA (mtDNA) sequence polymorphism. A 546-bp fragment of the mtDNA D-loop region was sequenced in 129 chickens from the areas of Vientiane, Luang Prabang and Pakse. In total, 29 haplotypes were identified and formed five clades. Haplotype diversity and nucleotide diversity of the native fowls in Laos were 0.85536±0.0172 and 0.010158±0.005555, respectively. Although the Laotian native fowls were distributed across five clades, most of them were clustered in two main clades (A and B), which were originated in China. The other haplotypes were contained in clades D, F, and I, which originated from continental southeast Asia. These results suggest that multiple maternal lineages were involved in the origin of domestic chicken in Laos. Moreover, there appear to be at least two maternal lineages, one from China and the other from the southeast Asian continent.

Indonesian native chickens are considered an important genetic resource, particularly with respect to their excellent traits for meat and egg production. However, few molecular genetic studies of these native chickens have been conducted. We analyzed the genetic diversity and differentiation of 4 populations of Indonesian native chickens: Black Kedu (BK), Kedu (KD), Kampung (LOC), and Arab (AR). Blood samples from 188 individuals were collected in central and western Java. Genomic DNA was genotyped using 98 autosomal SNP markers, of which 87 were found to be polymorphic. The proportion of polymorphic loci and the average heterozygosity of each population were in the range of 0.765 to 0.878 and 0.224 to 0.263, respectively. The 4 populations of Indonesian chickens appeared to be derived from 3 genetic populations (K = 3): maximum likelihood clustering showed that the BK variety and AR breed were each assigned to a distinct cluster, whereas the LOC ecotype and KD variety were admixed populations with similar proportions of membership. Principal components analysis revealed that eigenvector 1 separated BK and AR from the other 2 populations. Neighbor-joining trees constructed from pairwise distance matrix (FST) estimates, for individuals and between populations, corroborated that the LOC ecotype and KD variety were related closely, whereas the BK variety and AR breed diverged at greater distances. These results also confirmed the usefulness of SNP markers for the study of genetic diversity.

Analysis of SNPs on the Z sex chromosome is thought to be a useful approach to estimate genetic diversity and genetic relationships in chicken populations. The objective of this research was to analyze the genetic diversity and genetic relationship of Indonesian native chicken populations. Here, we genotyped six unlinked SNP loci on the Z chromosome of 103 hens and 85 cocks from the four populations of Indonesian native chickens: Black Kedu (BK), Kedu (KD), Kampung (LOC), and Arab (AR). Genetic diversity and matrix pairwise distance FST were computed for 23 BK, 116 LOC, 20 AR, and 29 KD chickens. Average expected heterozygosity was greater in LOC and KD than BK and AR. The lowest pairwise FST value was estimated at 0.028 (P

【In this study, to examine genetic variability within a breed and genetic relationships between populations/breeds, we genotyped 606 birds from seven Japanese native chicken breeds at seven polymorphic loci of egg white proteins and compared those with Asian native chicken populations and commercial breeds. Genotyping of the Japanese native breeds showed that ovalbumin, two ovoglobulins and ovotransferrin were polymorphic, but ovomacroglobulin, ovoflavoprotein and lysozyme were monomorphic. The proportion of polymorphic loci ( $P_{poly}$ ) and average heterozygosity ( $\bar{H}$ ) within a population ranged from 0.286 to 0.429 and from 0.085 to 0.158, respectively. The coefficient of gene differentiation ( $G_{ST}$ ) was 0.250 in the Japanese native chicken breeds. This estimate was higher than that of Asian native chicken populations ( $G_{ST}$ = 0.083) 0.083) and of commercial breeds ( $G_{ST}$ = 0.169) 0.169). Dendrogram and PCA plot showed that Satsuma-dori, Jitokko, Amakusa-daio and Hinai-dori were closely related to each other and grouped into Asian native chickens and that Tsushima-jidori, Nagoya and Chan (Utaichan) were ramified far from other Japanese native chicken breeds. The egg white protein polymorphisms demonstrated that the population differentiation of the seven Japanese native chicken breeds was relatively large.】

Six polymorphic sites of the bovine prion protein gene (PRNP) were genotyped in 569 animals of Asian native cattle, Japanese breeds, purebred mythun (Bos frontalis), and mythun x cattle composite animals. At the 23-bp indel site, a deletion (23-) allele was a major allele in all populations except mythun. At the 12-bp indel site, an insertion (12+) allele was a major allele in all populations. The 14-bp indel site was polymorphic in all Asian native cattle. In the octapeptide repeat region, a six-repeat allele was a major allele in all populations, and 5/5 and 4/6 genotypes were detected in Japanese Black and Mongolian cattle and in mythun, respectively. Two nonsynonymous single nucleotide polymorphisms (SNPs) (K3T and S154N) were detected in Asian native cattle and mythun. Haplotype analysis using the genotypes of the six sites estimated 33 different haplotypes. The haplotype 23- 12- K 6 S 14+ was found in all populations.

Polymorphisms in the prion protein gene (PRNP) are known to be associated with transmissible spongiform encephalopathies in human, sheep and goats. There is tentative association between PRNP promoter polymorphism and bovine spongiform encephalopathy (BSE) susceptibility in cattle. In this study, we genotyped for six bovine PRNP polymorphic sites including a 23-bp indel in the promoter, a 12-bp indel in the intron 1, two nonsynonymous single nucleotide polymorphisms (SNPs), octapeptide repeats in the coding region and a 14-bp indel in the 3'-untranslated region in 178 animals representing Japanese Brown, Kuchinoshima feral, Mishima, Japanese Shorthorn and Holstein. In 64 Japanese Brown cattle, three indel sites were polymorphic. All of the six sites were monomorphic in Kuchinoshima. The 23-bp and 12-bp indel sites were polymorphic in Mishima cattle. The 23-bp and 14-bp indel sites were polymorphic in Japanese Shorthorn cattle. Both SNP sites were monomorphic in all cattle examined in this study. At the 23-bp indel site, the genotype frequencies of Japanese Brown and Holstein breeds were similar to that of BSE affected cattle. We estimated 12 different haplotypes from these genotypic data. A '23-12-K6S14+' haplotype was the major haplotype in all populations, whose frequencies ranged from 0.50 to 1.00.

Plumage, shank color and comb shape of 617 native chickens were recorded at four ethnic settlements in Xishuangbanna Dai Autonomous Prefecture, Yunnan Province, China. The frequencies of genes controlling these morphological characters were calculated from the phenotypes of all 617 birds observed. In all settlements, the frequency of dominant white (I) was low, whereas the frequencies of wild type (e+) for the extended black locus (E, e+, e) were highest. The gene frequencies of shank color (Id, id) and comb type (P, p) changed in relation to the ethnicity of the human residents.

The gene constitution of polymorphisms of the four calpain genes (µ-calpain, m-calpain, p94, and µ/m-calpain) were analyzed in South-East Asian native chickens, White Leghorn and Broiler commercial chickens, and Red and Green jungle fowl. Polymorphisms were detected at all loci in chickens and Red jungle fowl, but only for CAPN1 (µ-calpain gene) in Green jungle fowl. CAPN2 and CAPN1.5 are linked on chicken chromosome 3, and the genotype for these loci were treated as haplotype. Some combinations of calpain loci were tested using principal component analysis, and the best combination (CAPN1, CAPN3, and CAPN1.5) was determined. The proportion of polymorphic loci (Ppoly) and heterozygosity ( ) were 1.00 and 0.316‐0.465 in domestic chickens and red jungle fowl, and 0.33 and 0.137 in Green jungle fowl, respectively. GST values suggested that the degree of subdivision among native chickens was relatively low except for Thailand, which was highest. Pair-wise FST testing, dendrogram and principal component analysis from the results of calpain loci showed that the four South-East Asian native and commercial chicken populations were close genetically.

Calpains are intracellular Ca2+-dependent proteases and enzymes that contribute to growth and meat quality. In the present study, we identified polymorphisms in four calpain genes (CAPN1, CAPN2, CAPN3, and CAPN1.5) expressed ubiquitously in chicken using polymerase chain reaction-restriction fragment length polymorphism, and mapped them using two backcross families (East Lansing (EL) and Kobe University (KU)). CAPN2 and CAPN1.5 mapped to two locations on chromosome 3 about 30 cM apart, while CAPN3 mapped to chromosome 5. CAPN1 was linked to a previously unlinked microsatellite marker LEI0140 to form a new linkage group called E66. CAPN2 and CAPN3 extend the amount of conserved synteny between chicken chromosome 3 and human chromosome 1, and between chicken chromosome 5 and human chromosome 15, respectively. Although CAPN2, CAPN3, and CAPN1.5 were found in the University of California Santa Cruz chicken genome browser gateway, CAPN1 and LEI0140 were not in specific genomic positions.

Three electrophoretic variations (AA, BB and AB) of ovalbumin controlled by codominant alleles OvA and OvB have been observed in various chicken populations. We compared nucleotide sequences of the open reading frame between two alleles of ovalbumin gene. The difference between the two alleles was found as a non-synonymous substitution of asparagine to aspartic acid as a result of AAT to GAT point mutation at position 8032–8034 in exon 8. We developed polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) protocol in combination with Mbo I restriction endnuclease mapping for the detection of this substitution. By the PCR-RFLP the allelic frequency of the OvB was estimated to be within the range of 0.000–0.150 in 11 Asian indigenous chicken populations and 0.000 in four improved breeds used in the present study. Gene frequency, estimated by PCR-RFLP in the present study, paralleled that obtained by protein polymorphisms of egg white. Thus, this study provides, for the first time, information of the occurrence of ovalbumin allele OvA and OvB in Asian indigenous chicken populations.

Cattle exhibit a range of carcass defects, including blood splash (BLS), intramuscular edema (INE), muscle steatosis (MUS), bruising (BR), trim loss (TRL) and others (OTH). These defects lower the carcass value and can result in significant economic loss to producers. We estimated the incidence, relationship with inbreeding coefficients and genetic parameters of carcass defects in Japanese Black cattle using 561 619 carcass records from Kagoshima, Japan during April 1988 through March 2011. The defect incidence ranged from 0.22% for TRL to 5.73% for BR. The incidence of MUS and BR increased from 1.21% to 6.57% and from 1.06% to 9.31%, respectively. The incidence of INE peaked at 7.44% in 1999 and decreased thereafter. We observed a positive linear relationship between the defect incidence and the inbreeding coefficients in MUS, BR and TRL (P0.01). The heritabilities estimated by univariate animal model with Gibbs sampling for BLS, INE, MUS, BR and TRL were 0.24, 0.06, 0.18, 0.05 and 0.02, respectively. The contribution of farm variance to phenotypic variance was negligible (0.01 to 0.04). Significant genetic correlations of TRL were estimated with MUS (0.63) and BR (0.63). Our results suggest that genetic factors contribute to the incidence of BLS and MUS.

Genetic variations of seven egg white protein loci in 1,112 samples from eight Asian countries (Yunnan province of China, Mongolia, Nepal, Vietnam, Laos, Thailand, Myanmar, Indonesia) and 360 samples from two improved breeds (Isa Brown, Boris Brown) were investigated by using starch gel and polyacrylamide gel electrophoresis. Five egg white protein loci (Oν, G 3 , G 2 , G 1 and Tf E W ) were found to be polymorphic in Asian native chicken populations. The proportion of polymorphic loci (P p o l y ) and average heterozygosity (H) of Asian native populations varied from 0.143 to 0.714 and 0.014 to 0.225, respectively, and were higher than those of improved breeds. The subdivision index (G S T ) value among 18 native chicken populations in Asia is lower (0.0827) than among improved chicken populations (0.1693). This value means that the degree of subdivision among Asian native populations is lower than among improved breeds and gene constitutions among populations in Asia are similar.

The morphological identification and ecological studies on the 3 subspecies of red jungle fowls were carried out in Thailand, Laos and Vietnam from 1994 to 1998. A total of 59 red jungle fowls and 47 hybrids with native chicken were collected and applied to the detailed morphological examination. For the ecological investigation, the hearing survey was performed at 55 localities. Fifty nine red jungle fowls were identified to 3 subspecies groups, Gallus gallus gallus with white earlobes, and G. g. spadiceus and G. g. jabouillei with red earlobes. The earlobe color was used as the most important index for the subspecies identification. Collecting places of individuals were also used as an effective index from the result of zoogeographical survey. There is an extensive zone of intergradation among the habitats of these 3 subspecies. The G. g. gallus inhabiting the continental Thailand, Cambodia, Laos and Vietnam expresses pure white earlobes covered completely with white patch, and the G. g. gallus inhabiting deep south Thailand expresses incomplete white earlobes.Therefore, the names of G. g. gallus type C (Continental) and G. g. gallus type I (insular) are reasonable to these zoogeographically differentiated two groups of G. g. gallus.

Insulin-like growth factor 1 receptor (IGF1R) is essential for the signalling of growth. In this study, we performed single nucleotide polymorphism (SNP) detection in the Japanese quail IGF1R coding region and an association study between SNPs and body weight in two lines (SS and LL) selected for large and small body weight. Of 21 SNPs obtained, a SNP at position AB292766:c.2293G>A led to the replacement of a valine with an isoleucine (V765I). The two lines were fixed for alternate alleles, with allele encoding valine fixed in the LL line. A significant effect of the SNP genotype was found on 10-week body weight (P < 0.01) and on 4- to 10-week and 6- to 10-week average daily gain (P < 0.05) in the F(2) family obtained from lines LL and SS. In six populations maintained in Japan or France, the frequency of allele encoding valine was higher than the allele encoding isoleucine.

Lysozyme is one of the best characterized antimicrobial proteins in egg white. Three phenotypes of egg white lysozyme in Japanese quail, Coturnix japonica, (namely fast; slow; and the combination, FS) were observed by acid polyacrylamide gel electrophoresis. The fast phenotype showed faster mobility on Acid-PAGE than the slow phenotype. Comparison of the coding sequences for lysozyme derived from the slow and fast phenotypes revealed a nonsynonymous SNP at nucleotide position 115 from the translation initiation site, which alters AA sequence of lysozyme. This nonsynonymous SNP converted glutamine (Q) in the slow phenotype to lysine (K) in the fast phenotype at AA residue 21 of mature lysozyme (Q21K). Here, we investigated the effect of these phenotypes on muramidase activity, antibacterial activity, and hatchability. Muramidase activity toward isolated cell walls of Micrococcus lysodeikticus was in the order: fast allozyme > slow allozyme > chicken (Gallus gallus), but no significant difference was found among the 3 (P > 0.05). Antibacterial activity against live Staphylococcus aureus cells was significantly greater for the fast allozyme than the slow allozyme from 20 h after incubation (P < 0.05). For the antibacterial effects against live Escherichia coli cells, the activity of fast was significantly higher than that of slow at 16 h after incubation (P < 0.05). Hatchability was estimated for reciprocal crosses of Japanese quail with the FF (fast) and SS (slow) genotypes. Hatchability was 92.5% in FF male × SS female crosses and 87.2% in SS male × FF female crosses. A Cochran-Mantel-Haenszel test revealed a significant difference between the crosses (P < 0.05) and indicated that the female-derived slow phenotype led to improved rates of hatching. Our results suggest that the nonsynonymous SNP in Japanese quail lysozyme influences the electrophoretic migration, muramidase activity, and antibacterial activity of the protein, in addition to the hatchability of the eggs. These results demonstrate, for the first time, a significant difference in antibacterial activity and hatchability between 2 lysozyme phenotypes in Japanese quail.

The efficiency of insertion and/or deletion (indels) polymorphisms as genetic markers was evaluated by genotyping 102 indels loci in native chicken populations from Myanmar and Indonesia as well as Red jungle fowls and Green jungle fowls from Java Island. Out of the 102 indel markers, 97 were polymorphic. The average observed and expected heterozygosities were 0.206 to 0.268 and 0.229 to 0.284 in native chicken populations and 0.003 to 0.101 and 0.012 to 0.078 in jungle fowl populations. The coefficients of genetic differentiation (Gst) of the native chicken populations from Myanmar and Indonesia were 0.041 and 0.098 respectively. The genetic variability is higher among native chicken populations than jungle fowl populations. The high Gst value was found between native chicken populations and jungle fowl populations. Neighbor-joining tree using genetic distance revealed that the native chickens from two countries were genetically close to each other and remote from Red and Green jungle fowls of Java Island. (Key Words: Genetic Markers, Indels Polymorphism, Jungle Fowl, Native Chicken)

BACKGROUND: Prion protein (PrP) level plays the central role in bovine spongiform encephalopathy (BSE) susceptibility. Increasing the level of PrP decreases incubation period for this disease. Therefore, studying the expression of the cellular PrP or at least the messenger RNA might be used in selection for preventing the propagation of BSE and other prion diseases. Two insertion/deletion (indel) variations have been tentatively associated with susceptibility/resistance of cattle to classical BSE. METHODOLOGY/PRINCIPAL FINDINGS: We studied the expression of each genotype at the two indel sites in Japanese Black (JB) and Japanese Brown (JBr) cattle breeds by a standard curve method of real-time PCR. Five diplotypes subdivided into two categories were selected from each breed. The two cattle breeds were considered differently. Expression of PRNP was significantly (p0.05). CONCLUSION: Our results suggest that the del/del genotype or at least its del allele may modulate the expression of PRNP at the 23-bp locus in the medulla oblongata of these cattle breeds.

Calpain activity was determined by western blot analysis of steady-state concentrations of m-calpain (calpain requiring millimolar Ca2+ for activation) and also by northern blot analysis of steady-state concentrations of mRNA encoding m-calpain in three lines of quail: a random-bred control line (RR) and two lines selected for body weight, one for increased body weight (LL) and another for decreased body weight (SS). The m-calpain activities in skeletal muscle were higher in the SS line and lower in the LL line. From western blot analysis, enzyme levels of calpain were almost the same for all three lines. At the level of gene expression, the mRNA concentration encoding m-calpain was higher in the LL and lower in the SS line. These results suggest that the regulation of calpain activity in skeletal muscle is a three-step process, regulation at the transcription level, regulation at the enzyme level, and regulation of the activation of calpain.

本研究は63世代にわたって体重の大(LL)および小(SS)の2方向へ選抜したウズラ系統ならびにそれらの対象群として維持してきた無作為交配集団(RR)について,血液中のパラサイロイドホルモン(PTH)およびCa++の濃度を測定し,その系統間差について検討を行った.血中PTH濃度はNichals Institute, co. Ltd.のintact PTHキットにより,またCa++濃度は原子吸光法により測定した.ウズラの血中Ca++濃度では雄で274,304および323ppm/ml,雌では868,891および949ppm/mlであり,系統間(P

体重について大小2方向に選抜されたウズラの系統を用いて,骨格筋におけるm-calpainおよびactin遺伝子のm-RNAの発現量の系統間の違いについて分析を行った.供試個体は幼若期の23日齢に屠殺され,ただちに胸筋を採取し,液体窒素で凍結した.全RNAはguanidinium thiocyanateで拙出し,またpoly (A) +RNAはoligo (dT) -cellulose columnで分離した.プローブとして,ヒトβ-actinのPst I断片(2.0kb)とニワトリm-calpainのPst I断片(1.1kb)を用いた.actinとm-calpainのm-RNAは,いずれも体重大系統(LL),対照系統(RR)および体重小系統(SS)の順に高いシグナルを示した,これらの結果から,ウズラの筋肉組織におけるm-calpainおよびactinのいずれの遺伝子においてもm-RNAの発現量には系統間で違いが存在することが明らかとなった.また,いずれの系統においても,actinの発現量がm-calpainの発現量に比べて高かった.

Genetic differences which exist in the prion protein gene (PRNP) have been reported to influence susceptibility of humans, sheep and goats to prion diseases. In cattle, however, none of the known coding polymorphisms has a direct effect on bovine spongiform encephalopathy (BSE). It has been reported that 23-bp insertion/deletion (indel) polymorphisms within the promoter region have a tentative association to BSE susceptibility in German cattle, and a lower number of 24-bp repeat units in the open reading frame (ORF) was reported to reduce BSE susceptibility in transgenic mice. In this study, because of the hypothesis that bovine PRNP promoter polymorphisms cause changes in PRNP expression, we genotyped PRNP polymorphisms in the promoter and intron 1 using 218 genomic DNA samples from two Japanese cattle breeds. We also analysed the expression levels of prion in 40 animals by quantification of real-time PCR using mRNAs extracted from the medulla oblongata to study the relationship between PRNP genotypes and PRNP expression. We found a significant correlation between promoter indel polymorphisms and PRNP-mRNA expression (P(0.0413)) and therefore hypothesize that differences in polymorphisms could be one of the causes of differences in PRNP expression levels. We also report a novel difference in PRNP expression (P < 0.0001) between Japanese Black and Japanese Brown cattle breeds. There was no significant difference based on age and sex of the animals.

体重大小選抜(LLおよびSS)ならびに無作為交配(RR)のウズラ系統を用いて,それらの系統の筋肉蛋白質代謝回転速度を明らかにし,さらに筋肉蛋白質代謝回転速度と関連を有すると思われる筋肉内のカルシウム依存性中姓プロテアーゼ活性値およびそのインヒビター活性値について分析を行なった.LL, RRおよびSS系統の筋肉蛋白質の分解速度は3週齢で2.1,4.0および9.5%/day,また8週齢で1.4,2.1および3.7%/dayと評価された.筋肉蛋白質の合成速度は3週齢で4,4,7.3および12.3%/day,また8週齢で3.2,2.8および3.9%/dayと計算された.これらの結果から,体重の小さい個体は大きい個体に比べて,相対的に高い代謝速度を有することが示唆された.LL, RRおよびSS系統のm-CANP活性値(unit/mg extractable muscle protein)は3週齢で0.503,0.788および1.146,また,8週齢で0.134,0,224および0.275と評価された.一方,CANPインヒビター活性値を測定すると,LL, RRおよびSSの各系統3週齢で0.196,0.150および0,098,また8週齢で0,157,0.120および0.079と評価された.これらの結果から,m-CANPおよびCANPインヒビター活性値は筋肉蛋白質の分解速度および体重と関連を有し,これらの活性値は体重の選抜に伴い変化したことを示唆している.

Deficiency of citrin, a liver-type mitochondrial aspartate-glutamate carrier (AGC), encoded by the SLC25A13 gene on chromosome 7q21.3, causes autosomal recessive disorders: adult-onset type II citrullinemia (CTLN2) and neonatal hepatitis associated with intrahepatic cholestasis (NICCD). So far, we have described 12 SLC25A13 mutations: 11 were from Japan and one from Israel. Three mutations found in Chinese and Vietnamese patients were the same as those in Japanese patients. In the present study, we identified a novel mutation IVS6+1G>C in a Japanese CTLN2 patient and widely screened 12 SLC25A13 mutations found in Japanese patients in control individuals from East Asia to confirm our preliminary results that the carrier frequency was high in Asian populations. Mutations 851–854del and 1638–1660dup were found in all Asian countries tested, and 851–854del associated with 290-haplotype in microsatellite marker D7S1812 was especially frequent. Other mutations frequently detected were IVS11+1G>A in Japanese and Korean, S225X in Japanese, and IVS6+5G>A in Chinese populations. We found a remarkable difference in carrier rates in China (including Taiwan) between north (1/940) and south (1/48) of the Yangtze River. We detected many carriers in Chinese (64/4169 = 1/65), Japanese (20/1372 = 1/69) and Korean (22/2455 = 1/112) populations, suggesting that over 80,000 East Asians are homozygotes with two mutated SLC25A13 alleles.

An attempt was made to assign five genes, CPS1, OTC, ASS, CRYD2, and ARG2, to chicken chromosomes (GGA) by radiation-hybrid mapping. OTC was assigned to GGA1; ARG2 to GGA5; CPS1 to GGA7; and CRYD2 to GGA19. ASS was not, however, assigned to a specific chromosomal position.