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Most QTL detection studies in pigs have been carried out in experimental F2populations. However, segregation of a QTL must be confirmed within a purebred population for successful implementation of marker-assisted selection. Previously, QTL for meat quality and carcass traits were detected on SSC 7 in a Duroc purebred population. The objectives of the present study were to carry out a whole-genome QTL analysis (except for SSC 7) for meat production, meat quality, and carcass traits and to confirm the presence of segregating QTL in a Duroc purebred population. One thousand and four Duroc pigs were studied from base to seventh generation; the pigs comprised 1 closed population of a complex multigenerational pedigree such that all individuals were related. The pigs were evaluated for 6 growth traits, 7 body size traits, 8 carcass traits, 2 physiological traits, and 11 meat quality traits, and the number of pigs with phenotypes ranged from 421 to 953. A total of 119 markers were genotyped and then used for QTL analysis. We utilized a pedigree-based, multipoint variance components approach to test for linkage between QTL and the phenotypic values using a maximum likelihood method; the logarithm of odds score and QTL genotypic heritability were estimated. A total of 42 QTL with suggestive linkages and 3 QTL with significant linkages for 26 traits were detected. These included selection traits such as daily BW gain, backfat thickness, loin eye muscle area, and intramuscular fat content as well as correlated traits such as body size and meat quality traits. The present study disclosed QTL affecting growth, body size, and carcass, physiological, and meat quality traits in a Duroc purebred population.

The quality of fat is an important factor in defining the quality of meat. Fat quality is determined by the composition of fatty acids. Among lipid metabolism-related genes, including fatty acid synthesis genes, several genetic variations have been reported in the bovine fatty acid synthase (FASN), stearoyl-CoA desaturase (SCD), sterol regulatory element-binding protein 1 (SREBP1), and GHgenes. In the present study, we evaluated the single and epistatic effects of 5 genetic variations (4 SNP and 1 insertion/deletion) in 4 genes (FASN, SCD, SREBP1, and GH) on the fatty acid composition of the longissimus thoracis muscle and carcass and meat quality traits in 480 commercial Japanese Black cattle. Significant single effects of FASN, SCD, and GHL127Vpolymorphisms on the fatty acid composition of the longissimus thoracis muscle were detected. The A293V polymorphism of SCDhad the largest effect on myristic acid (C14:0, P< 0.001), myristoleic acid (C14:1, P< 0.001), stearic acid (C18:0, P< 0.001), oleic acid (C18:1, P< 0.001), and MUFA (P< 0.001). Polymorphisms in the FASN, SCD, and SREBP1genes showed no effect on any meat yield trait. There were no significant epistatic effects on fatty acid composition among pairs of the 3 genes (FASN,SCD, and SREBP1) involved in fatty acid synthesis. No epistatic interactions (P> 0.1) were detected between FASNand SCDfor any carcass trait. When the genotypes of 3 markers (FASN,SCD, and GHL127V) were substituted from the lesser effect allele to the greater effect allele, the proportion of C18:1 increased by 4.46%. More than 20% of the genetic variance in the C18:1 level could be accounted for by these 3 genetic markers. The present results revealed that polymorphisms in 2 fatty acid synthesis genes (FASNand SCD) independently influenced fatty acid composition in the longissimus thoracis muscle. These results suggest that SNP in the FASNand SCDgenes are useful markers for the improvement of fatty acid composition in commercial Japanese Black cattle.

We performed a whole genome QTL analysis to confirm the existence of QTL affecting fatty acid composition and to investigate the effects of additive, dominance, imprinting, and epistatic interactions between QTL in an F2resource population. The F2population, comprising 166 pigs, was obtained by crossing a Duroc boar and a Meishan sow. The F2population was measured for fatty acid composition and was used for whole genome QTL analysis, using a total of 180 microsatellite markers. The suggestive and significant thresholds were equivalent to likelihood ratio test statistics (LRT) of 13.7 and 20.5, respectively. For single QTL analysis, 2 suggestive QTL and 1 significant QTL were detected. Suggestive QTL for C14:0 and C16:1 were identified on chromosomes 12 and 7, respectively, and a significant QTL for C18:2 was detected on chromosome 5 with the greatest LRT of 22.9. For C14:0, a significant QTL with paternal imprinting effect was also detected on chromosome 12, where the locus was in the same region as an additive QTL effect, with a large LRT of 24.2. The suggestive QTL on chromosome 7 was not significant when correction for backfat thickness was included. For epistatic QTL analysis, a total of 5 epistatic pairs were located on chromosomes 4, 5, 9, and 16. The same epistatic pairs were significant when correction for backfat thickness was included. The individual QTL identified in the single QTL analysis and in the epistatic QTL analysis were not the same loci, except for C18:2. For C14:0, an epistatic QTL pair was detected on chromosome 16, with the least P-value of 4.9 × 10−12. The present study constitutes one of the first reports on the mapping of imprinted QTL and epistatic pairs of QTL affecting fatty acid composition in a swine population.

Many QTL analyses related to meat production and meat quality traits have been carried out using an F2resource population produced by crossing 2 genetically different breeds. This experiment was intended to investigate whether these QTL were segregating in a purebred Duroc population that had been selected for meat production and meat quality traits during 7 generations. Sus scrofachromosome 7, for which significant QTL of intramuscular fat and many other traits have already been reported, was studied. The polymorphism of 10 microsatellite markers that were arranged at about 20-cM intervals was investigated on 1,004 pigs. In the selected population, 954 progeny were produced from mating of 99 sires and 286 dams. The QTL analysis for a full-sib family population was examined with the multigeneration pedigree structure of the population. Variance component analysis was used to detect QTL in this population and was examined for the multigeneration pedigree population. In this study, multigenerational pedigree estimated identical by descent coefficients among sibs were produced using Markov chain Monte Carlo methods. The maximum likelihood of odds score was found at the 70-cM position for the LM area, at the 0-cM position for the pork color standard, and at the 120-cM position for the number of thoracic vertebra, but no significant QTL for intramuscular fat were detected on SSC 7. These results indicate that QTL analysis via a variance component method within a purebred population was effective to determine that QTL were segregating in a population of purebred Durocs.

High performance LSIs embedded with ferroelectric random access memory (FeRAM) for contactless IC cards are now commercially available. The emphasis is placed on the materials solution with SrBi2(Ta,Nb)2O9 (SBTN) which enables to exploit the potential performance of FeRAMs for composite logic/microcontroller LSIs operating at high speeds and low powers. The leading-edge 0.6-μm and double-level-metal FeRAM technology produces microcontroller-embedded LSIs with 14-kbit or 64-kbit FeRAM. A mature 0.8-μm and single-level-metal process has been built to maximize the die yield. Yields exceeding 90% indicate the excellent process stability. Product qualification data have proven the robust FeRAM technologies.

We have successfully incorporated the ferroelectric and the high dielectric constant capacitors into integrated circuits. The GaAs MMICs with BST capacitors have been widely used for cellular phones. The BST technology is also applied to a silicon CCD delayline processor for VCRs and camcorders. With respect to the ferroelectric technology with Y1, an experimentally fabricated 256k bit FeRAM has exhibited the remarkable performance of the 100 ns and 3V operation with a 1T/1C cell configuration dedicated for the FeRAM. These integrated ferroelectrics have been achieved by controlling the ferroelectric properties in thin films and incorporating the films into GaAs and silicon devices with outstanding process technology. Furthermore, we refer to the memory cell design technology which enables the FeRAM to work below 1V. Various advantages of low-voltage and high-speed operation inherent in integrated ferroelectrics will be emphasized on the intelligent microelectronics applications toward the next multimedia generation.

Ferroelectric non-volatile memories (FENVM) are fabricated using spin-coat and fire deposition of the SrBi2Ta2O9 layered perovskite ferroelectric. Test memories using a 2 transistor-2 capacitor bit cell, top contacts to capacitors and single level metal were fabricated. We report here on the integration and electrical characteristics of fully functional 1 Kbit test memories.

The monounsaturated fatty acid percentage, especially oleic acid, is 1 of the important traits for beef quality because it has positive effects on beef palatability and human health. In our previous study, we selected 100 animals with the highest and 100 animals with the lowest oleic acid percentage from 1,836 animals, and performed pool-based, genome-wide association study (GWAS), using Illumina BovineSNP50 BeadChip v2 to identify genomic regions associated with oleic acid percentage (ISAG conference 2014). GWAS analysis revealed 2 novel candidate regions for oleic acid percentage; 3 and 1 significant SNP on BTA9 and BTA14, respectively, were detected at 5% genome-wide significance level. The objective of this study was to confirm these significant SNPs detected by pooling method and to validate the candidate regions for fatty acid composition. We genotyped the most significant SNPs in each region (Hapmap60557-rs29018515 on BTA9 and BTB-00554873 on BTA14), using 444 animals selected randomly from 1,836 animals. Association analysis showed that the both SNPs on BTA9 and BTA14 were significantly associated with oleic acid percentage (P= 0.0004 and p< 0.0001, respectively). In addition, Tukey-Kramer’s honestly significant difference test revealed that T/T genotype in Hapmap60557-rs29018515 indicated 1.31 higher percentage of oleic acid than C/C genotype; A/A genotype in BTB-00554873 indicated 1.23 higher percentage of oleic acid than C/C (p< 0.05). Our results suggested that these SNPs would be the effective DNA markers for oleic acid percentage in Japanese Black cattle. Further investigation on gene polymorphisms in these candidate regions may lead to identification of the causative mutation for oleic acid percentage.

Female fertility, a fundamental trait required for animal reproduction, has gradually declined in Japanese Black cattle. The objective of this study was to identify genomic regions associated with female fertility traits in Japanese Black cattle. We performed a DNA pool-based genome-wide association study (GWAS) to estimate the associations between genotypes and 3 fertility traits (age at first calving, calving interval, number of calves produced at 4 yr of age), using Illumina BovineSNP50 Beadchip v2. In the GWAS analyses, 100 animals with the highest and 100 animals with the lowest values in each trait were selected from 3,973 animals, based on pedigree and phenotypic information, and then pooled as the high and low groups, respectively. The GWAS revealed that 1 SNP on BTA 5 was associated with age at first calving and 2 SNPs on BTA 12 and 20 were associated with calving interval at 5% significance level. To confirm the significant differences of allele frequencies between high and low groups in each SNP, we individually genotyped the SNPs for high and low groups. The statistical analysis revealed that there were significant differences (P< 0.05) in each SNP. In the present study, we performed further analysis, using 1 of 3 SNPs (Hapmap53957-rs29016480 on BTA12). To evaluate the effect of the SNP, we genotyped the SNP using 516 animals randomly selected from 3,596 animals and investigated the association with calving interval by analysis of variance. As a result, this SNP showed significant effects on calving interval (P= 0.0118). In addition, Tukey-Kramer HSD test revealed significant differences between AA (n= 212) and GG (n= 52) genotypes (p< 0.05), and the animals with GG type had 24.07 d shorter calving interval than the animals with AA type. Thus, the result suggests that this SNP could be used as a marker to select Japanese Black cattle with superior calving interval.

Beef marbling is an important trait that determines the grade of meat quality. Recent studies suggested that fat percentage in ribeye area, which is measured by image analysis, would be an attractive alternate for evaluation of beef marbling. The objective of this study was to identify genomic regions associated with fat percentage in ribeye area using a DNA pool-based genome-wide association study in Japanese Black cattle. One hundred animals with the highest and 100 animals with the lowest values were selected from 1,836 animals, based on corrected phenotype, and then pooled as the high and low groups, respectively. We performed a DNA pool-based genome-wide association study, using Illumina BovineSNP50 BeadChip v2 with 3 replicate assays for each pooled sample. Genome-wide association study (GWAS) revealed that 6 SNPs on BTA10 were found to be associated with fat percentage at 5% chromosome-wide significance level (P= 4.31E-5). The most significant SNP (BTB-01047707) were further evaluated by individual genotyping to validate the pooling method. We genotyped the SNP by PCR-RFLP method, using 567 animals randomly selected from 1,836 animals and investigated the allelic effect on fat percentage. Tukey–Kramer method using a least mean square value of each genotype revealed that there were significant differences among TT (n= 46), TC (n= 234), and CC (n= 287) genotypes (p< 0.0001). The animals with TT type had 5.5% higher values than CC type. These results confirmed the significant SNP detected by pooling GWAS and this SNP can be used in marker-assisted selection. This information will also be useful to select candidate genes for beef marbling in future studies.