摘要:

Summary.Restriction fragment length polymorphism (RFLP). of ovine casein genes was investigated. Genomic DNA from 56 rams was digested with 10 restriction endonucleases and Southern blots probed with the four ovine casein cDNAs (αs1‐,ß‐, αs2‐and k‐Cn). Five enzymes, namely,BglI,PvuII,RsaI,TaqI andHindIII revealed nine different RFLPs. The inheritance of six of these polymorphisms was studied by segregation analysis of gametes in nine rams' families, and each of them could be related to the existence of alleles at the relevant casein locus. A close linkage between the four ovine casein genes was demonstrated since no recombination within the four pairs of loci examined, αs1‐ß‐Cn, αs1‐k‐Cn, ß‐k‐Cn and αs2‐k‐Cn, was observed in the progeny of double heterozygous rams. The casein genes are thus clustered in the ovine species

ISSN:0268-9146    

DOI:10.1111/j.1365-2052.1991.tb00641.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Summary.Methods have been devised for detecting polymorphisms in the bovine ß‐and k‐casein genes using the polymerase chain reaction (PCR) followed either by restriction enzyme digestion (to reveal a restriction fragment length polymorphism (RFLP)). or by hybridization of an allele‐specific oligonucleotide. These methods, as well as being faster and more sensitive than traditional RFLP methods, are of more general applicability since they can detect any change in DNA sequence. They require only a small sample of blood or semen and are applicable to animals of any age or sex. These methods make possible large‐scale screening and thus selection for alleles at these loci. Typing of blood DNA can give erroneous results when the animal concerned is a twin; however, this can be overcome by retesting using milk or semen. Analysis of the k‐casein genotype of Holstein‐Friesian bulls gives frequencies for the A and B alleles of 0.80 and 0.20 respectively. Selection in favour of the B allele, which is superior for cheese production, could thus have a large effect. The A3and B alleles at the ß‐casein locus have been shown to be rare in the Holstein Friesian population. Linkage disequilibrium exists between ß‐casei

ISSN:0268-9146    

DOI:10.1111/j.1365-2052.1991.tb00642.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Summary.By using seven endonucleases and four bovine cDNA probes specific for αs1‐,αs2‐,ß‐, and K‐casein genes, nine restriction fragment length polymorphisms (RFLPs) have been found in the sheep orthologous DNA regions. In contrast to the low level of variation observed at the protein level, these DNA polymorphisms determine a high level of heterozygosity and, therefore, represent useful tools for genetic analyses since they can also be obtained without the need for gene expression. In fact, informative matings suggest that in sheep, as in cattle, the four loci

ISSN:0268-9146    

DOI:10.1111/j.1365-2052.1991.tb00643.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Summary.The genetic structure of the bovine major histocompatibility complex (MHC) was investigated using the lymphocyte microcytotoxicity test for class I typing and the mixed lymphocyte culture (MLC) assay for class II typing. Using locally produced alloantisera and antisera from the Third International BoLA Workshop, 14 class I BoLA‐A locus alleles were identified in the study population, a single herd of approximately 700 Holstein‐Friesian cattle. Eleven of these were alleles recognized in the International Workshop and three were new alleles. An MLC titration assay was employed in conjunction with class I typing to define BoLA haplotypes and identify BoLA complex homozygotes. An embryo transfer family consisting of eight full sibling cattle including one BoLA complex homozygote was produced by half sibling mating. Five other BoLA complex homozygotes were subsequently identified in the herd. Six MLC defined class II haplotypes investigated in detail were designated BoLA‐D1, D2, D3, D4, D5 and D7. BoLA‐D1 was associated with the class I specificity BoLA‐Aw6, D2 with Aw6 and the new class I specificity Ac3, D3 with Aw6 and Aw11, D4 with Aw10, D5 with Aw31 and Aw11, and D7 with Aw20. The discovery of four groups of class I identical‐class II disparate haplotypes, and three pairs of class I disparate‐class II identical haplotypes indicates the presence of considerable complexity in the BoLA complex that is not detected using cla

ISSN:0268-9146    

DOI:10.1111/j.1365-2052.1991.tb00644.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Summary.The identification of breeding stocks of Atlantic eels presents a dilemma which should be solved by genetic analyses. The eye lens crystallins are encoded by a family of genes which differentiate vertebrates. The eye lens tissue from two Atlantic eels,Anguilla anguillaandA. rostrata,and a Pacific control,A. japonica,were separated by electrofocusing. The isoelectric points (pI) of 34 lens protein bands were calibrated. The distributions of those proteins in the sampled populations supplement the existing evidence on the genetic diversity of eels and support the original biometrical description of two Atlantic species.

ISSN:0268-9146    

DOI:10.1111/j.1365-2052.1991.tb00645.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Summary.Restriction fragment length polymorphism (RFLP) analysis was used to characterize the ß‐globin cluster in Norwegian dairy goats. In 122 individuals, different RFLP patterns were detected after BglII andPstI digestion and hybridization with acaprineß‐globin probe. The location of the polymorphicBglII andPstI sites were determined. The different RFLPs were in linkage disequilibrium with each other and with the ß‐globin locus as studied at the protein level. A preferential association between certain RFLP haplotypes and ß‐globin variants was observed.Polymorphic DNA fragments in the e‐globin genes were detected afterMspI digestion and hybridization with acaprinee‐probe, and eight different band patterns were observed. Correlation between differentMspI haplotypes and the ß‐globin varia

ISSN:0268-9146    

DOI:10.1111/j.1365-2052.1991.tb00646.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Summary.Haemoglobin (Hb) phenotypes have been studied in 100 wild European mouflons living on the island of Sardinia by means of isoelectric focusing (pH 6.7‐7.7 range) of the native tetramers, acid‐urea‐Triton gel‐electrophoresis, and reversedphase HPLC of globin chains. The result indicates the presence of two ß‐globin alleles one of which, corresponding to the ßB, being the most common(f=0.94). None were carriers of the earlier described Hb A. The new Hb was provisionally named Hb M. Severely anaemic mouflons were able to synthesize Hb C at expense of the Hb B alone, thus suggesting structural and physiological homologies between mouflon ßBand sheep ßAglobin genes, and between the newly observed ßMallele and the ßBof the domestic

ISSN:0268-9146    

DOI:10.1111/j.1365-2052.1991.tb00647.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Summary.Fast protein liquid chromatography (FPLC) and polyacrylamide gel electrophoresis were used to determine the ratio betweenIα‐andIIα‐globin chains in Norwegian dairy goats. Three different phenotypes, designated normal (N) withIα‐ toIIα‐globin ratio 3:1, reversed (R) with ratio 1:2 and double‐reversed (RR) with noIα‐globin, were described. Family studies indicated that the R animals were heterozygous, and the RR animal homozygous, for a haplotype without a functionalIα‐globin product. Southern blot analysis of goat DNAs digested with six different restriction enzymes showed that the different ratios of α chain expression could not be due to a deletion of theIα‐gene and/or duplication or triplication of theIIα‐globin genes. The homozygous reversed animal with no detectableI

ISSN:0268-9146    

DOI:10.1111/j.1365-2052.1991.tb00648.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Summary.Blood samples of 70 foxes, including 10 families, have been investigated by horizontal starch gel electrophoresis for the enzymes adenosine deaminase (ADA) and mannose phosphate isomerase (MPI). The observed variation of the enzymes could be explained as a result of one locus with two codominant alleles and one with three respectively. The segregation in the families of the alleles assumed for the two loci is in accordance with this genetic model. The frequency of the two alleles at theAdalocus is about the same and the slowest anodic migrating allele at theMpilocus is the most frequent.

ISSN:0268-9146    

DOI:10.1111/j.1365-2052.1991.tb00649.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Summary.The distribution of transferrin (Tf) and haemoglobin (Hb) polymorphisms in five goat breeds in the USA is reported. Two Tf types, A and B, were identified. A significant difference in frequency(P<0.05) was observed only between the Spanish and Alpine goats. Haemoglobin ß‐globin variants, HbßA, HbßD and HbßE were observed with isoelectric focusing at pH ranges 5–8 and 6.7‐7.7. HbßD was not found in the Alpine and Angora breeds. Haemoglobin allelic frequencies varied widely and differed significantly(P<0.05) am

ISSN:0268-9146    

DOI:10.1111/j.1365-2052.1991.tb00650.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY