[Show abstract][Hide abstract] ABSTRACT: The balancers of Drosophila melanogaster are widely used in genetic research. By analyzing the phenotype of offspring from hybridization of chapped wing (L) mating with OR, 982p and e, respectively, we mapped the chapped wing mutation on chromosome 3 for the first time and demonstrated the chapped wing mutation as a new balancer of D. melanogaster with dominant wing nicking phenotype. Finally, we bred a novel gathering line with double balancers of L and Cy in D. melanogaster. The mutant L provided a legible dominant marker for the balancer of chromosome 3, and the cultivation of double balancers chapped-curly wing enriches the balancer stock, which is often used in mapping and screening.
[Show abstract][Hide abstract] ABSTRACT: Curly is a easily distinguishable dominant mutant wing character. The Cy mutation is the most commonly used dominant marker for the second chromosome balancers in Drosophila melanogaster, but little is known about the Cy gene. Based on known genomic and cytogenetic information, a 102 bp deletion which is located between the Genes synaptotagmin (syt) and Activin Like Protein at 23B(Alp23B) on the Drosophila melanogaster genome (release 4) had been found to be commonly contained on Cy chromosome in three different curly strains. Meanwhile, when using the deletion as a DNA marker, the result suggested that Cy homozygote be lethal in embryo period. These results will provide some helpful information to investigate molecular mechanism of curly wings in the further study.
[Show abstract][Hide abstract] ABSTRACT: The classical White (I) locus is one of the important pig coat color hereditable loci,which is homologous to KIT gene. In this study,PCR-RFLP and PCR-SSCP analysis were commanded on the Intron 17 and 18 nucleotide sequences of KIT gene. The tested results showed that the substitution mutation (G-->A) of Intron 17 was found in white pigs, including Wuzhishan pigs (white), Landrace and Large White,and its genotype (AB) frequency was 1.1 and 0.8 respectively. The genotype frequency was uniformly 0 in the other native pig breeds. Similarly,the deleted mutation (AGTT) of Intron 18 was also found in the same white pigs,its genotype (,AA) frequency was 1.1 and 0.93 separately,while in the other native pig breeds was 0. Accordingly it was considered that KIT gene was an important factor regulating the white coat color genotype, and the classical I locus (KIT gene) was epistatic to the other genetic coat color loci. On the other hand,although the native pig breed Rongchang Pig is similar to Landrace and Large White in phenotype (white coat color), the mutation status found in them was absolutely distinct. So it is presumed that the coat color genetic system of Chinese native pig breeds was different from that of imported breeds.
[Show abstract][Hide abstract] ABSTRACT: With ESTs from porcine fatty tissue and cDNA sequences from human, bovine and mouse in non-reduncdant database and dbEST in GenBank,we sampled cDNA sequences of 70 function-known genes in four species on the base of randomly sampling method, analyzed the mutation pattern of 70 x 150 bp linking sequences between them, and established an integrated phylogenic analysis method. The results showed that 391 single bases mutations were found in 70 x 150 bp linking sequences alignment among four species. The number of mutation bases between them were greatly exceeded the 1/1000 predicted in the human genome analysis. C/T(T/C) and A/G (G/A) transitions were the major types of single base mutation. The genetic relationship between pig and bovine who are both Artiodactylous is the nearest, the next is human, and the farthest is mouse. The differentiation sequence taken place in four species from the same ancestor is that mouse is the earliest one, and the latter human, and pig and bovine are the latest.
[Show abstract][Hide abstract] ABSTRACT: The study of the molecular regulation mechanism of melanin synthesis during animal development has become a new focus recently . The synthesis and production of melanin during animal development are regulated by many genes. This paper summarized the molecular function mechanism of melanocortin-1-receptor (MC1R) gene and the relationship between the consequences of polymorphic variation of the gene and melanin traits, in addition to summarized the identification and mutation of MC1R gene in birds. Furthermore, the melanin synthesis mechanism in birds is also discussed here.
[Show abstract][Hide abstract] ABSTRACT: In animal breeding, microsatellite marker plays an important role in constructing genetic maps, QTL mapping and function analysis of structural genes. Myostatin, also known as GDF8, is a negative regulator of skeletal muscle mass and, in swine, it is evidenced to be related to birth weight and average daily gain from 60 kg to 100 kg of body weight. In present study, by subcloning and sequencing,we identified a novel microsatellite marker which is useful for fine QTL mapping for meat traits. A BAC clone containing porcine MSTN was extracted and digested with EcoR I to recover the fragment of > 4 kb for subcloning in pGEM-3zf (+). Sequencing and alignment results showed that this subcloned fragment was not from porcine MSTN, but included a tandem repeat of (TG) 13, which is a novel microsatellite marker (GenBank accession number: AF454400) flanking MSTN. To exclude its vector origin we designed specific primers flanking this marker and successfully amplified this fragment from porcine genome. Through a pedigree analysis of a double-muscled Yorshire strain, we found that it is inherited in a co-dominant manner. We also checked the gene frequencies of this locus in 381 unrelated individuals of 7 pig breeds, namely Laiwu,Landrace, Yorkshire,Duroc, Peterian, Min and Erhualian. Only two alleles were detected, the repeating number of which are 13 (allele A) and 19 (allele B) respectively, which indicated that it is a low poly morphic microsatellite marker. In addition, the frequencies of the two alleles are different between the two types of pig breeds, while allele A is dominant in Chinese local breeds, allele B is dominant in imported breeds. Alignment with AY208121 indicate that this locus is located 42 kb downstream of porcine MSTN. We speculate that this microsatellite DNA is an important marker both in fine QTL mapping for meat traits and in the expression study of porcine MSTN.
[Show abstract][Hide abstract] ABSTRACT: Polydactyly is a common abnormal limb phenotype in vertebrate and there is similar limb phenotype among different species. Research shows that polydactyly has a similar development mechanism, and this kind of polydactyly character seems to be controlled by homologous genes among species. The latest research results on human and mouse further shows that PPD should be caused by the disruption of a long range cis-acting regulator for Shh within Lmbr1 intron. Here the development mechanism and related genes controlling polydactyly character of vertebrate are reviewed.
[Show abstract][Hide abstract] ABSTRACT: Combining the technique of multiplex-PCR and the fluorescent semi-automated detection, a large-scale genome scanning was performed for 440 chickens, which was derived from China Agricultural University chicken resource families, within three generations. Fifty-five microsatellite markers were analyzed for this study. Those 55 microsatellite loci accorded with the characters of Mendelian co-inheritance. The heterozygosities ranged from zero to 0.89, with 72% of loci having a heterozygosity of more than 0.60. The polymorphism information content (PIC) ranged from 0 to 0.85, in which 70% of those loci had a PIC of more than 0.50 but their distribution varied in line A and line C. The allele frequency was significantly different between line A and line C at most loci (P < 0.01). At the same time, gene accordance inclination was found in line C. The Nei population resemble coefficient and standard genetic distance were 0.1002 and 0.8928.
[Show abstract][Hide abstract] ABSTRACT: Created Restriction Site PCR (CRS-PCR) is a simple and efficient method to identify SNP genotypes. One or more mismatch bases are used in a primer to create a restriction site by combining SNP site after PCR. The CRS-PCR products can be genotyped with a way the same as PCR-RFLP. In the study, Extracellular fatty acid binding protein (EX-FABP) gene was served as an example for establishing the CRS-PCR method. Strategy of CRS-PCR was also discussed.
[Show abstract][Hide abstract] ABSTRACT: A pair of primers was designed according to the sequence of mammal fatty acid binding protein (FABP) gene, then PCR amplified to chicken genome. After the product of PCR was cloned and sequenced, homologous comparison was done among porcine heart fatty acid binding protein gene and porcine adipocyte fatty acid binding protein gene. The result showed that the sequence of chicken FABP gene had 68% and 75% homology with porcine H-FABP and A-FABP gene respectively, and had 75% homology with porcine AFABP on amino acid level. The result of Northern showed that the gene only expressed in fat tissues.
[Show abstract][Hide abstract] ABSTRACT: In this experiment, F2 chicken derived from Broilers crossing with Silky was used to study the effect of insulin-like growth factor-II gene on growth and carcass traits. The partial gene was amplified by two pairs of primers, and single nucleotide polymorphism (SNPs) was detected by the technique of restriction fragment length polymorphism (RFLP), and then confirmed by DNA sequencing. The mutation was found in the exon-2 of the gene, and can be clarified by cutting of restriction enzyme Aci-I. The result of least square analysis showed the gene was significantly related with growth and carcass traits. It implied that the insulin-like growth factor-II gene could be a genetic locus or linked to a major gene affecting greatly the growth and carcass traits in chicken.