Huntington's disease (HD) is an inherited autosomal dominant neurodegenerative disorder caused by an expansion of a CAG trinucleotide repeat in the huntingtin (HTT) gene [Huntington's Disease Collaborative Research Group (1993) A novel gene containing a trinucleotide repeat that is expanded and unstable on Huntington's disease chromosomes. The Huntington's Disease Collaborative Research Group. Cell, 72, 971-983]. Despite identification of the gene in 1993, the underlying life-long disease process and effective treatments to prevent or delay it remain elusive. In an effort to fast-track treatment strategies for HD into clinical trials, we have developed a new large-animal HD transgenic ovine model. Sheep, Ovis aries L., were selected because the developmental pattern of the ovine basal ganglia and cortex (the regions primarily affected in HD) is similar to the analogous regions of the human brain. Microinjection of a full-length human HTT cDNA containing 73 polyglutamine repeats under the control of the human promotor resulted in six transgenic founders varying in copy number of the transgene. Analysis of offspring (at 1 and 7 months of age) from one of the founders showed robust expression of the full-length human HTT protein in both CNS and non-CNS tissue. Further, preliminary immunohistochemical analysis demonstrated the organization of the caudate nucleus and putamen and revealed decreased expression of medium size spiny neuron marker DARPP-32 at 7 months of age. It is anticipated that this novel transgenic animal will represent a practical model for drug/clinical trials and surgical interventions especially aimed at delaying or preventing HD initiation. New sequence accession number for ovine HTT mRNA: FJ457100.

Animal GeneticsVolume 35, Issue 2 p. 163-163 Physical mapping of the stearoyl-CoA desaturase (SCD) locus in sheep H. Kuchel, H. Kuchel Animal Science, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, AustraliaSearch for more papers by this authorB. D. Siebert, B. D. Siebert Animal Science, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, AustraliaSearch for more papers by this authorC. D. K. Bottema, C. D. K. Bottema Animal Science, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, AustraliaSearch for more papers by this authorG. C. Webb, G. C. Webb Animal Science, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, AustraliaSearch for more papers by this authorA. M. Crawford, A. M. Crawford AgResearch, Molecular Biology Unit, Biochemistry Department, University of Otago, Box 56, Dunedin, New ZealandSearch for more papers by this authorS. J. Duncan, S. J. Duncan AgResearch, Invermay Agricultural Centre, Private Bag 50034, Mosgiel, New ZealandSearch for more papers by this authorP. A. McDonald, P. A. McDonald AgResearch, Molecular Biology Unit, Biochemistry Department, University of Otago, Box 56, Dunedin, New ZealandSearch for more papers by this authorJ. C. McEwan, J. C. McEwan AgResearch, Invermay Agricultural Centre, Private Bag 50034, Mosgiel, New ZealandSearch for more papers by this authorW. S. Pitchford, W. S. Pitchford Animal Science, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, AustraliaSearch for more papers by this author H. Kuchel, H. Kuchel Animal Science, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, AustraliaSearch for more papers by this authorB. D. Siebert, B. D. Siebert Animal Science, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, AustraliaSearch for more papers by this authorC. D. K. Bottema, C. D. K. Bottema Animal Science, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, AustraliaSearch for more papers by this authorG. C. Webb, G. C. Webb Animal Science, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, AustraliaSearch for more papers by this authorA. M. Crawford, A. M. Crawford AgResearch, Molecular Biology Unit, Biochemistry Department, University of Otago, Box 56, Dunedin, New ZealandSearch for more papers by this authorS. J. Duncan, S. J. Duncan AgResearch, Invermay Agricultural Centre, Private Bag 50034, Mosgiel, New ZealandSearch for more papers by this authorP. A. McDonald, P. A. McDonald AgResearch, Molecular Biology Unit, Biochemistry Department, University of Otago, Box 56, Dunedin, New ZealandSearch for more papers by this authorJ. C. McEwan, J. C. McEwan AgResearch, Invermay Agricultural Centre, Private Bag 50034, Mosgiel, New ZealandSearch for more papers by this authorW. S. Pitchford, W. S. Pitchford Animal Science, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, AustraliaSearch for more papers by this author First published: 17 March 2004 https://doi.org/10.1111/j.1365-2052.2004.01114.xCitations: 4 W. S. Pitchford ([email protected]) Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume35, Issue2April 2004Pages 163-163 RelatedInformation

Bim is a proapoptotic protein of the Bcl-2 family that shares only the short BH3 domain with other members. It has three isoforms, apparently produced by alternative splicing. The demonstration that Bim is essential for certain apoptotic responses and to prevent overproduction of hematopoietic cells suggests that it may be a tumor suppressor. We have, therefore, investigated the organization of the mouse Bim gene, delineating its promoter and splicing, and positioned the gene on both mouse and human chromosomes. Bim has six exons, but the third is a facultative intron that is spliced out in the mRNAs for the smaller isoforms (BimL and BimS), but not that encoding the largest isoform (BimEL). The 0.8-kb region 5′ to exon 1, which contains a TATA-less promoter and binding sites for several transcription factors, can drive expression of a reporter gene. Mouse Bim localizes to the distal third of Chromosome (Chr) 2, near the F-G boundary, and its human counterpart to Chr 2q12 or q13. Deletions of these bands have been reported in ten tumors (eight hematopoietic), reinforcing the possibility that Bim is a tumor suppressor. These findings should help to clarify the regulation of Bim expression and to assess whether mutations involving Bim contribute to neoplastic and other diseases.

The recently characterized human serine protease, Testisin, is expressed on premeiotic testicular germ cells and is a candidate type II tumor suppressor for testicular cancer. Here we report the cloning, characterization and expression of the gene encoding mouse Testisin, Prss21. The murine Testisin gene comprises six exons and five introns and spans ≈ 5 kb of genomic DNA with an almost identical structure to the human Testisin gene, PRSS21. The gene was localized to murine chromosome 17 A3.3‐B; a region syntenic with the location of PRSS21 on human chromosome 16p13.3. Northern blot analyses of RNA from a range of adult murine tissues demonstrated a 1.3 kb mRNA transcript present only in testis. The murine Testisin cDNA shares 65% identity with human Testisin cDNA and encodes a putative pre‐pro‐protein of 324 amino acids with 80% similarity to human Testisin. The predicted amino‐acid sequence includes an N‐terminal signal sequence of 27 amino acids, a 27 amino‐acid pro‐region, a 251 amino‐acid catalytic domain typical of a serine protease with trypsin‐like specificity, and a C‐terminal hydrophobic extension which is predicted to function as a membrane anchor. Immunostaining for murine Testisin in mouse testis demonstrated specific staining in the cytoplasm and on the plasma membrane of round and elongating spermatids. Examination of murine Testisin mRNA expression in developing sperm confirmed that the onset of murine Testisin mRNA expression occurred at ≈ day 18 after birth, corresponding to the appearance of spermatids in the testis, in contrast to the expression of human Testisin in spermatocytes. These data identify the murine ortholog to human Testisin and demonstrate that the murine Testisin gene is temporally regulated during murine spermatogenesis.

The Eph family of receptor tyrosine kinases plays a crucial role during development and is implicated in oncogenesis. Using a partial cDNA clone of an Eph-related kinase (Esk) we isolated the complete coding region of a gene which we show to be murine EphA1 by both structural and functional criteria. The chromosomal localization is shown to be syntenic to hEphA1 and the genomic organization also shows distinct features found in the hEphA1 gene. Functionally, in keeping with findings for the human homologue, both soluble recombinant and "native" mEphA1 show preferential binding to ephrin A1. However, we also observed significant binding to other A-type ligands as has been observed for other Eph receptors. We analysed the expression of mEphA1 mRNA by in situ hybridization on tissue sections. mEphA1 was expressed in epithelial elements of skin, adult thymus, kidney and adrenal cortex. Taken together with previous Northern blotting data these results suggest that mEphA1 is expressed widely in differentiated epithelial cells.

We have cloned the complete coding region for a human homologue of the Drosophila melanogaster sluggish-A and yeast PUT1 genes, previously shown to encode proline oxidase activity in these organisms. The predicted 516-residue human protein shows strong homology (51% amino acid sequence identity) to the D. melanogaster protein, indicating that this new human gene may encode proline oxidase. Northern analysis shows that the gene is expressed in human lung, skeletal muscle and brain, to a lesser extent in heart and kidney, and weakly in liver, placenta and pancreas. The gene was mapped by fluorescence in situ hybridization and by in situ hybridization with a [3H]-labelled DNA probe to chromosome 22q11.2, a region previously implicated in type-I hyperprolinaemia in a case of CATCH 22 syndrome, a contiguous gene deletion syndrome involving 22q11. Taken together, the evidence indicates that this new human gene is a good candidate gene for type-I hyperprolinaemia. In view of the neurological phenotype of the D. melanogaster sluggish-A mutant, it is of interest that schizophrenia and bipolar disorder susceptibility genes also map in this region.

Activating mutations in the ras genes are commonly found in a wide range of human tumors. We recently cloned two mammalian genes, Son of sevenless 1 (mSos1) and Son of sevenless 2 (mSos2), whose protein products appear to be important positive regulators of ras proteins. Given the proposed role of Sos proteins in ras regulation, and the frequent occurrence of activated ras alleles in tumor cells, we were interested in determining whether the Sos genes may also be activated inappropriately by DNA rearrangement in tumor cells. To investigate this possibility, we have determined the chromosomal locations of both the mouse and the human Sos1 and Sos2 genes, using a combination of genetic linkage analysis and in situ hybridization to chromosomal spreads. We find that the murine Sos1 and Sos2 genes map to chromosomes 17E and 12C3.3-D and their human counterparts to chromosomes 2p21-2p2 and 14q21, respectively. Neither the human nor the mouse Sos loci map close to known mutations or to regions showing consistent karyotypic abnormalities in tumor cells.

The glutathione transferases (GSTs) are involved in the metabolism of a wide range of compounds of both exogenous and endogenous origin. There is evidence that deficiency of GST may increase sensitivity to certain environmentally derived carcinogens. In contrast, elevated expressoin has been implicated in resistance to therapeutic drugs. The GSTs are the products fo a several gene families. This review summarized the present knowledge of the genetic onterrelationships between the various isoenzymes, their deficiences and the physical locations of their genes.

Three families are reported showing transmission of a previously described variant, which is not associated with any clinical abnormality. The variant involves additional material at the band 9p12, which shows homogeneous staining of intermediate density with GTL- and RBG-banding, and negative staining with CBG-banding. The region stains positively with Feulgen stain. In situ hybridization with total genomic human DNA, cloned alpha satellite, satellite III, and ribosomal DNA all show no hybridization to the 9p12 variant. Two members of one of the families show the largest 9p12 variant yet reported; two other carriers in this family have inherited a variant of decreased size. It is suggested that the 9p12 variants are homogeneously staining regions. Using the ISCN three-letter convention, this variant could be described as hsr(9)(p12).

We characterized a recombinant clone E7 containing a 1.6-kb Eco RI insert of human alpha satellite DNA (alpha DNA) which hybridized in situ predominantly to the centromere of chromosome 17. Three thousand copies of this sequence were detected on chromosome 17, although a lesser number of copies were also found on the centromeres of chromosomes 11, X, and the other human chromosomes, except Y. In the human genome, sequences homologous to E7 were organized principally as five major polymorphic (Pst I) forms of tandem alpha DNA repeats with molecular weights between 2.0 and 2.7 kb. We We studied the higher-order organization of these major forms using a series of 12 cosmid clones. Close linkage of the different polymorphic forms was demonstrated, with no two cosmids showing an identical linkage pattern. Six of the cosmid clones carried a considerable amount (20-25%) of nonhomologous (non-alpha) DNA, indicating that the repeat arrays are relatively frequently interrupted by other genomic DNA. In none of the cosmid inserts were the repeat arrays bound on both sides by non-alpha DNA, suggesting that short arrays are not common. However, some of the intervening non-alpha DNA sequences were relatively short, and vary in size from 6 to 24 kb. Our results suggest an irregular and complex pattern of organization of alpha DNA in the human genome.