[Impact of diagnostic ureteroscopy and biopsy on radical nephroureterectomy of upper tract urothelial carcinoma].

OBJECTIVE: To investigate the impact of preoperative diagnostic ureteroscopy and biopsy (UB) on radical nephroureterectomy (RNU) and the prognosis of upper tract urothelial carcinoma (UTUC). METHODS: The clinical data of UTUC patients receiving RNU between Jan. 2007 and Dec. 2016 were retrospectively collected. The median follow up time was 40 months. The operation time and blood loss of RNU were compared between UB group and non-UB group. Subgroup analyses were conducted according to the time interval between UB and RNU, and surgery methods of lower ureter. The linear regression model was used to adjust for other common factors that impacted operation time. RESULTS: A total of 163 UTUC patients were included in the final analysis. For the lower ureter, open ureterectomies were performed in 91 patients (55.9%), while retroperitoneal laparoscopic ureterectomies were performed in 72 patients (44.1%). A total of 110 (67.5%) patients received preoperative UB. Compared with non-UB group, the average operation time of UB group was significantly longer [(252.5±79.8) min vs. (221.3±79.8) min, P=0.019], but no difference of blood loss was found (median, 50 mL vs. 50 mL, P=0.143). In subgroup analysis, the average operation time of RNU was significantly prolonged when RNU was performed after 1 week of UB (P=0.023). Meanwhile, the median blood loss of RNU increased significantly when it was done after 2 weeks of UB compared with non-UB group (100 mL vs. 50 mL, P=0.012). UB was also significantly prolonged the operation time of RNU in retroperitoneal laparoscopic ureterectomy group (P=0.012). In multivariable analysis, UB (P=0.049), ≥pT3 (P=0.039), pN+ (P=0.018) and ureterectomy method (P=0.005) were independent risk factors of prolonged operation time. The 3-year cancer specific survival (CSS) rate was 87.2% in our cohort. UB had no significant impact on cancer specific survival (P=0.435). CONCLUSION: UB was an independent risk factor of prolonged RNU time, but did not significantly influence cancer specific survival of upper tract urothelial carcinoma patients.

[Perirenal cystic lymphangioma in an adult: a case report and literature review].

Lymphangioma is a rare, benign mesenchymal neoplasm, which is characterized by numerous intercommunicating cystic spaces containing lymphatic fluid. It is considered a congenital disease resulting from the obstruction of regional lymph drainage during the developmental period. Lymphangioma frequently occurs in the cervical neck and axilla, also in the retroperitoneum, mediastinum, mesentery, omentum, colon, and pelvis, rarely in the perirenal space. These tumors usually present in childhood, but infrequently, these also present in adults. Patients often complain of hematuria, flank pain, or abdominal pain. Complications of lymphangioma have been reported to include infection, ruputure, or hemorrhage. There are three types of lymphangioma commonly identified: capillary, cavernous, and cystic. Cystic type is the one commonly found intra-abdominally or retroperitoneally, and may be uniloculated or multiloculated. All these perirenal tumors have a very low incidence, make it difficult to diagnose. Differential diagnosis must be performed with the primary renal lymphoma, urinoma, polycystic kidney, teratoma, both benign and malignant tumors, etc. Endoscopic ultrasound guided fine needle aspiration is recommended in some literatures, which may help make diagnosis and further guide subsequent therapeutic strategy. Regarding treatment, surgical excision can be performed via either laparotomy or laparoscopy. And injection of sclerosants into lympahgioma has been described in the literature in nonsurgical candidates. The optimal definitive treatment is total surgical excision. Despite being rare, the tumor has an excellent prognosis. Here, we report a case of a 48-year-old woman with a left renal mass found in an abdominal ultrasonography during a health checkup. In the case presented, abdominal ultrasonography and magnetic resonance urography (MRU) revealed an approximately 11.3 cm×10.6 cm×12.8 cm multilocular cystic mass in the left perirenal space. There was no history of bowel or bladder complaint, either previous illness episodes. Full blood count and kidney function tests were within normal limits. Laparoscopic surgical removal of the cyst was accomplished without incident. A benign cystic perirenal lymphangioma was diagnosed on histology and confirmed with immunohistochemical stains. One month after the surgery the ureteral stent was removed. The patient was free of disease after a 3-month follow-up period. We report the case and discuss the management of perirenal lymphangiomatosis with a literature review.

[Ureteroscope can assist risk stratification in upper tract urothelial carcinoma].

OBJECTIVE: To analyze the efficiency of ureteroscope and biopsy in the diagnosis of tumor grade, muscle-invasiveness and multifocality in suspected upper tract urinary carcinoma (UTUC) patients in order to find out whether it can be used in the risk stratification of UTUC patients. METHODS: A retrospective study of 76 UTUC patients who underwent preoperative ureteroscope and/or biopsy and received radical nephroureterectomy in Peking University Third Hospital during January 2014 to December 2016 was undertaken. RESULTS: In this study, 76 patients were included. There were 31 males (40.8%), and 45 females (59.2%). The median age was 64.5 years (31-88), and 51 patients had the symptom of hematuresis. The tumor was located in renal pelvis in 39 patients, and in ureter in 37 patients. Post-operative pathology confirmed that all the 76 patients included in this study suffered from UTUC, of whom 21 (21.6%) were of low-grade, 51 (67.1%) were of high-grade, 4 (5.3%) were undetermined, and 47 (61.9%) patients were muscle-invasive, and 27 (35.5%) were not, and 2 (2.6%) were undetermined. Among the 50 patients, in whom the grade of the tumor could be diagnosed by biopsy, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value for low-grade tumor was 88.2%, 69.7%, 76.0%, 60.0% and 92.0%, respectively. Among the 27 patients, in whom the muscle-invasiveness could be diagnosed by biopsy, 5 patients were diagnosed with muscle-invasiveness, all confirmed by pathology after surgery and 22 patients were diagnosed with none muscle-invasiveness, turned out to be 50% muscle-invasive and 50% none-muscle invasive after surgery. The accuracy was 59.3%. The accuracy of ureteroscopic biopsy to diagnosis multifocality was 61.0%. On univariate analysis, biopsy grade was associated with postoperative pathology (P=0.001), while gender, age, side, body mass index (BMI), hematuresis, preoperative estimated glomerular filtration rate (eGFR), hydronephrosis, tumor size, location, multifocality and sessile were not associated with postoperative pathology grade. Biopsy grade (P=0.02), preoperative eGFR<90 mL/(min×1.73 m2)(P=0.025) and tumor located in pelvis (P=0.049) were associated with muscle invasiveness. Gender, age, side, BMI, hematuresis, hydronephrosis, tumor size, multifocality and sessile were not significantly associated with muscle invasiveness. CONCLUSION: Ureteroscope and biopsy can assist risk stratification in upper tract urothelial carcinoma patients.

[Analysis of the efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation in patients with myelodysplastic syndrome with blastomycosis and survival comparison of different subtypes after the WHO 2022 reclassification].

Objective: To evaluate the efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with myelodysplastic syndrome accompanied by myelodysplasia (MDS-EB) and to compare the prognosis of different subtypes of patients classified by World Health Organization (WHO) 2022. Methods: A total of 282 patients with MDS-EB who underwent allo-HSCT at the Hematology Hospital of the Chinese Academy of Medical Sciences from October 2006 to December 2022 were included in the study. The WHO 2022 diagnostic criteria reclassified MDS into three groups: myelodysplastic tumors with type 1/2 of primitive cell proliferation (MDS-IB1/IB2, 222 cases), MDS with fibrosis (MDS-f, 41 cases), and MDS with biallelic TP53 mutation (MDS-biTP53, 19 cases). Their clinical data were retrospectively analyzed. Results: ① The median age of 282 patients was 46 (15-66) years, with 191 males and 91 females. Among them, 118 (42% ) and 164 (58% ) had MDS-EB1 and MDS-EB2, respectively. ②Among the 282 patients, 256 (90.8% ) achieved hematopoietic reconstruction after transplantation, with 11 (3.9% ) and 15 (5.3% ) having primary and secondary implantation dysfunctions, respectively. The cumulative incidence of acute graft-versus-host disease (GVHD) 100 days post-transplantation was (42.6±3.0) %, and the cumulative incidence of grade Ⅱ-Ⅳ acute GVHD was (33.0±2.8) %. The cumulative incidence of chronic GVHD 1 year post-transplantation was (31.0±2.9) %. Post-transplantation, 128 (45.4% ), 63 (22.3% ), 35 (12.4% ), and 17 patients (6.0% ) developed cytomegalovirus infection, bacteremia, pulmonary fungal infection, and Epstein-Barr virus infection. ③The median follow-up time post-transplantation was 22.1 (19.2-24.7) months, and the 3-year overall survival (OS) and disease-free survival (DFS) rates were 71.9% (95% CI 65.7% -78.6% ) and 63.6% (95% CI 57.2% -70.7% ), respectively. The 3-year non-recurrent mortality rate (NRM) is 17.9% (95% CI 13.9% -22.9% ), and the 3-year cumulative recurrence rate (CIR) is 9.8% (95% CI 6.7% -13.7% ). The independent risk factors affecting OS post-transplantation include monocyte karyotype (P=0.004, HR=3.26, 95% CI 1.46-7.29), hematopoietic stem cell transplantation complication index (HCI-CI) of ≥3 points (P<0.001, HR=2.86, 95% CI 1.72-4.75), and the occurrence of acute gastrointestinal GVHD of grade Ⅱ-Ⅳ (P<0.001, HR=5.94, 95% CI 3.50-10.10). ④The 3-year OS and DFS rates in the MDS-IB1/IB2 group post-transplantation were better than those in the MDS-biTP53 group [OS: 72.0% (95% CI 63.4% -80.7% ) vs 46.4% (95% CI 26.9% -80.1% ), P=0.020; DFS: 67.4% (95% CI 60.3% -75.3% ) vs 39.7% (95% CI 22.3% -70.8% ), P=0.015]. The 3-year CIR was lower than that of the MDS-biTP53 group [7.3% (95% CI 4.3% -11.4% ) vs 26.9% (95% CI 9.2% -48.5% ), P=0.004]. The NRM at 3 years post-transplantation in the MDS-IB1/IB2, MDS-f, and MDS-biTP53 groups were 16.7% (95% CI 12.1% -22.1% ), 20.5% (95% CI 9.4% -34.6% ), and 26.3% (95% CI 9.1% -47.5% ), respectively (P=0.690) . Conclusion: Allo-HSCT is an effective treatment for MDS-EB, with monomeric karyotype, HCI-CI, and grade Ⅱ-Ⅳ acute gastrointestinal GVHD as independent risk factors affecting the patient's OS. The WHO 2022 classification helps distinguish the efficacy of allo-HSCT in different subgroups of patients. Allo-HSCT can improve the poor prognosis of patients with MDS-f, but those with MDS-biTP53 have a higher risk of recurrence post-transplantation.

Closing a gap in the physical map of the ovine major histocompatibility complex.

A 184 kb gap in an ovine MHC physical map was successfully closed by identification of two overlapping clones (304C7 and 222G18) from a Chinese fine wool merino sheep BAC library. The location and tiling path of the two clones were confirmed by BAC-end sequencing and PCR amplification of loci in overlapping regions. Full-length sequencing of the clones identified 13 novel ovine genes in the gap between loci Notch4 and Btnl2, and eight of them belonging to the Butyrophilin-like (Btn-like or Btnl) gene family. The scattered distribution of the Btnl gene cluster at the gap provided a clue to explain the difficulties previously experienced in closing the gap. Completed BAC contigs of the ovine MHC will facilitate sequencing of the entire ovine leukocyte antigen (OLA) region, providing detailed information for comparative studies of MHC evolution.

[Allogeneic donor-derived CD19 CAR-T therapy of relapsed B-cell acute lmphoblastic leukemia after allogeneic hematopoietic stem cell transplantation].

Objective: To investigate the long term efficacy and side effects of a donor-derived CD19 chimeric antigen receptor (CAR) T-cell (HI19α-4-1BB-ζ CAR-T) therapy in the treatment of patients with relapsed B-cell acute lymphoblastic leukemia (B-ALL) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: A total of 9 subjects with relapsed B-ALL post allo-HSCT received donor-derived CD19 CAR-T therapy from July 2017 to May 2020. All subjects were infused with donor CD3-positive T cells after lymphodepletion chemotherapy, and a median dose of CAR-T cells was 1.79 (range, 0.86-3.53) ×10(6)/kg. Results: ①All subjects achieved complete remission and MRD-negative at 28-42 d post CAR-T cells infusion. ②Cytokine releasing syndrome (CRS) occurrd in all subjects and was grade 3 in 2, grade 2 in 4, grade 1 in 3 cases respectively. Four subjects developed immune effector cell-associated neurotoxicity syndrome (ICANS) , which was grade 2 in 1, grade 1 in 3. One subject developed grade IV acute graft-versus-host disease (GVHD) , and side effects were all controllable. ③Four subjects relapsed at a median period of 8.6 (4.6-19.3) months, 2 subjects died of disease progression after receiving chemotherapy and another one also died of disease progression 14 months after a second transplant, only 1 subject achieved complete remission after CD22 CAR-T cell therapy. Until last follow-up date, 6 subjects were leukemia-free and achieved complete donor chimerism. The estimated 1-year and 2-year leukemia-free survival (LFS) rate was 63.5% and 50.8%, with a median LFS of 18.1 months. ④After a median follow-up of 25.1 (range, 6.9-36.7) months, the estimated 2-year and 2.5-year OS rate were 87.5% and 52.5%, respectively. Conclusion: The donor-derived CD19 CAR-T cell therapy obtain a high remission rate in relapsed B-ALL patients post allo-HSCT with tolerable side effects, half subjects survived more than 2 years without disease recurrence, though long-term efficacy requires further observation. Chinese Clinical Trial Registry: ChiCTR1900025419.

Mps1 kinase regulates tumor cell viability via its novel role in mitochondria.

Targeting mitotic kinase monopolar spindle 1 (Mps1) for tumor therapy has been investigated for many years. Although it was suggested that Mps1 regulates cell viability through its role in spindle assembly checkpoint (SAC), the underlying mechanism remains less defined. In an endeavor to reveal the role of high levels of mitotic kinase Mps1 in the development of colon cancer, we unexpectedly found the amount of Mps1 required for cell survival far exceeds that of maintaining SAC in aneuploid cell lines. This suggests that other functions of Mps1 besides SAC are also employed to maintain cell viability. Mps1 regulates cell viability independent of its role in cytokinesis as the genetic depletion of Mps1 spanning from metaphase to cytokinesis affects neither cytokinesis nor cell viability. Furthermore, we developed a single-cycle inhibition strategy that allows disruption of Mps1 function only in mitosis. Using this strategy, we found the functions of Mps1 in mitosis are vital for cell viability as short-term treatment of mitotic colon cancer cell lines with Mps1 inhibitors is sufficient to cause cell death. Interestingly, Mps1 inhibitors synergize with microtubule depolymerizing drug in promoting polyploidization but not in tumor cell growth inhibition. Finally, we found that Mps1 can be recruited to mitochondria by binding to voltage-dependent anion channel 1 (VDAC1) via its C-terminal fragment. This interaction is essential for cell viability as Mps1 mutant defective for interaction fails to main cell viability, causing the release of cytochrome c. Meanwhile, deprivation of VDAC1 can make tumor cells refractory to loss of Mps1-induced cell death. Collectively, we conclude that inhibition of the novel mitochondrial function Mps1 is sufficient to kill tumor cells.

Using PCR to Distinguish Diaporthe phaseolorum and Phomopsis longicolla from Other Soybean Fungal Pathogens and to Detect Them in Soybean Tissues.

Restriction fragment length polymorphism analyses of polymerase chain reaction (PCR) amplified DNA were used to distinguish Diaporthe phaseolorum and Phomopsis longicolla isolates from other soybean fungal pathogens. Primers made to the conserved sequences of nuclear ribosomal DNA amplified the internal transcribed spacer (ITS) regions of D. phaseolorum var. meridionalis and P. longicolla. The PCR products were cloned and then sequenced. Specific-primers, Phom.I and Phom.II, were designed from the polymorphic regions of D. phaseolorum and P. longicolla isolates from soybean to distinguish them from other soybean fungal pathogens. These ITS-derived primers amplified a 337-bp-specific DNA fragment from P. longicolla, D. phaseolorum var. meridionalis, D. phaseolorum var. caulivora, D. phaseolorum var. sojae, and Phomopsis spp. from 20 different hosts. No amplified product was observed using DNA of seven other soybean fungal pathogens or soybean DNA. The detection limit of PCR using primers Phom.I and Phom.II was 2.5 × 10-7 dilution of fungal DNA extracted from samples of 10 pooled seeds and as low as a 1:15 (Phomopsis:soybean) ratio when using 10 ng of DNA per µl from each P. longicolla and soybean. PCR did not produce products using primers Phom.I and Phom.II with DNA extracted from noninfected seeds, but specific bands were observed from samples of 10 pooled seeds and from individually infected seeds. A specific band was observed as well from DNA extracts of tissue samples from symptomless plants inoculated with P. longicolla and D. phaseolorum var. sojae.

The clinical application of human bone matrix gelatin.

This paper reports the results of 24 cases of bone defect resulting from bone tumor or tumor condition excision, and of posterior spinal fusion, treated by human bone matrix gelatin. The success rate of bone defect repair and spinal fusion is 91.67%. The results suggest that human bone matrix gelatin has excellent osteoinductive effect and is ideal substitute for bone autografts.

[Transdermal permeability of estradiol through human skin of different body regions in vitro].

Transdermal permeability of estradiol was carried out by using Valia-Chien double-compartment permeation cell for the following 6 skin regions with intact and without stratum corneum: chest, abdomen, hip, upper arm, thigh and back. The estradiol permeation rates and accumulative amounts within 72 h in vitro were examined by HPLC. The results showed that the permeation rates of intact skin from different regions of the body were significantly different (P less than 0.01), and for the skins without stratum corneum over different regions, the permeation rates or the permeation amounts were about 18-55 times higher than that for the intact skin. The results demonstrated that the stratum corneum acts as the rate-limiting barrier in the skin permeation of estradiol, and that the difference in estradiol permeation rates for different skin regions was mainly caused by the different extents of the barrier.

Comparative analysis of 82 expressed sequence tags from a cattle ovary cDNA library.

In total, 82 ESTs were generated from 51 unique clones randomly selected from a cattle ovary cDNA library. Among these clones, 22 (42.1%) had 5' and/or 3' ends that matched with known human or other mammalian coding sequences, 18 (35.3%) matched human or other ESTs, and 11 (21.6%) represented novel transcripts with no significant match to any sequence in the databases. The relatively high frequency of ESTs with no matches in GenBank or dbEST indicates that bovine ovary may be a source of novel candidate genes for loci affecting cattle reproduction traits. Primers were designed for 11 ESTs that had human orthologs in GenBank. These ESTs were mapped to 10 bovine autosomes by PCR screening of a somatic cell hybrid panel. Among these 11 ESTs, 4 corresponded to genes previously mapped in humans and had chromosome assignments on the bovine map that were consistent with available comparative mapping data. Although the human orthologs of the remaining 7 mapped bovine ESTs have not been mapped, the human map location could be predicted on the basis of existing comparative mapping data. Because of the general utility of our approach for comparative genome analysis, we have termed it comparative mapping by annotation and sequence similarity (COMPASS). With the cost of large-scale EST sequencing becoming more affordable, and the rapid expansion of DNA databases, it is likely that COMPASS will be a preferred strategy for high throughput comparative mapping.

Sequence polymorphisms in the chemokines Scya1 (TCA-3), Scya2 (monocyte chemoattractant protein (MCP)-1), and Scya12 (MCP-5) are candidates for eae7, a locus controlling susceptibility to monophasic remitting/nonrelapsing experimental allergic encephalomyelitis.

Experimental allergic encephalomyelitis (EAE), the principal animal model of multiple sclerosis, is genetically controlled. To date, 13 disease-modifying loci have been identified in the mouse by whole genome scanning using an F2 intercross between EAE-susceptible SJL/J and EAE-resistant B10.S/DvTe mice. Two quantitative trait loci (QTL), eae6 and eae7, on chromosome 11 were identified by classical marker-specific linkage analysis and interval mapping. Both QTL were reported to be associated with severity and duration of clinical signs. eae7 was subsequently shown to be a unique locus controlling the development of monophasic remitting/nonrelapsing EAE. In this study, composite interval mapping resolved eae6 into two linked QTL: eae6a at 0-13 cM is associated with disease severity, and eae6b at 19-28 cM associated with the duration of clinical signs. Additionally, composite interval mapping significantly refined the locations of eae6a, eae6b, and eae7, thereby facilitating systematic candidate gene screening by cDNA sequencing of SJL/J and B10.S/DvTe alleles. Sequence polymorphisms were not seen in Lif and IL12 beta, candidate genes for eae6a and eae6b, respectively. Similarly, cDNA sequence polymorphisms in Nos2, Scya3, Scya4, Scya5, Scya6, Scya7, Scya9, Scya10, and Scya11 were excluded as candidates for eae7. However, multiple sequence polymorphisms resulting in significant amino acid substitutions were identified in Scya1 (TCA-3), Scya2 (monocyte chemoattractant protein (MCP)-1), and Scya12 (MCP-5). Given the role of chemokines in EAE, these sequence polymorphisms are promising candidates for eae7, a locus associated with severity of clinical signs and susceptibility to the shorter, less severe monophasic remitting/nonrelapsing form of disease.

Physical mapping of the autoimmune disease susceptibility locus, Bphs: co-localization with a cluster of genes from the TNF receptor superfamily on mouse chromosome 6.

An important approach to understanding complex diseases is to reduce them into well-characterized subphenotypes that are under monogenic control. One such example is Bordetella pertussis toxin-induced histamine sensitization in mice, a subphenotype of experimental allergic encephalomyelitis and experimental allergic orchitis. This subphenotype is controlled by a single locus, Bphs, previously mapped to a 33 cM region on mouse Chromosome (Chr) 6. We achieved considerable reduction of this candidate region and constructed a YAC contig across the refined interval. Our results demonstrate that Bphs is located between D6Mit151 and a newly developed marker, EC108RR, a region containing a small cluster of genes belonging to the TNF receptor superfamily. Sequence and quantitative analysis of the candidate gene, tumor necrosis factor receptor 1 (Tnfr1, p55), indicates that it is unlikely to be Bphs. However, the location of Bphs, together with physiologic effects it shares with Tnfr1 activation, suggest that Bphs may prove to be another member of the TNF receptor superfamily.

A panel of polymorphic bovine, ovine and caprine microsatellite markers.

A panel of 81 new polymorphic bovine microsatellite markers is described, together with further information on a previously reported group of 16 markers. The mean polymorphism information content of the 97 markers determined in 20 cattle was 0.66. Seventy-three of these markers have been assigned to chromosomes by either linkage analysis or use of hybrid cell panels. Thirty-nine of the markers were polymorphic in sheep, and 32 were polymorphic in goat. This study identified a set of 18 robust markers that were polymorphic in all three species and that covered 14 bovine chromosomes. This provides a single group of markers, which would be suited to genetic distance analysis and parentage control in cattle, sheep and goat.

Isolation and characterization of 45 polymorphic microsatellites from the bovine genome.

A small-insert bovine genomic library was constructed in pBluescript II SK(+) and enriched for microsatellites by selective rescue of single-stranded pBluescript DNA carrying (CA)n/(TG)n tandem repeats. Approximately 50% of the clones in the enriched library contained (CA)n repeats or CA-rich sequences. Sequencing of clones selected for (CA)n repeats resulted in the identification and characterization of 45 (CA)n polymorphic microsatellites. Genotyping in 9 large paternal half-sib families indicated that 40 of these microsatellite markers exhibit autosomal Mendelian inheritance. The numbers of alleles range from 2 to 18, with an average of 6.3 per locus. The polymorphic microsatellite markers we have identified and characterized will contribute to the construction of a high-resolution linkage map of bovine genome.

Development and mapping of microsatellites from a microdissected BTA 11-specific DNA library.

A chromosome-specific library was developed for Bos taurus autosome 11 by chromosome microdissection and microcloning using a bovine primary fibroblast culture, obtained from a t(X;23) heifer, that spontaneously developed a translocation chromosome involving bovine chromosome 11. The library was screened using (AC)12 oligos, positive clones selected, sequenced and primers developed to generate bovine chromosome 11-specific microsatellite markers. This study suggests that chromosome-specific libraries have great potential for development of microsatellite markers for the construction of marker-saturated linkage maps for each chromosome.

Report of the first workshop on the genetic map of bovine chromosome 23.

A report of the first workshop on the genetic map of bovine chromosome 23 (BTA23) is given. Five laboratories contributed data from 29 loci, including a total 11586 informative genotypes. The combined pedigrees represented 1930 potentially informative meioses. Eighteen of the 29 loci were common to two or more data sets and were used to construct a framework linkage map of BTA23. Twelve of the 18 could be ordered on the linkage map with a likelihood ratio of greater than 1000:1. Thus, a low resolution consensus map was constructed with a high level of support for order. The sex-averaged, female and male maps span 54.5, 52.7 and 55.8 cM, respectively. Sex-specific differences in recombination frequency were identified for eight pairs of framework loci. Average genetic distance between framework loci on the sex-averaged map is 5.0 cM.

A male linkage map of the cattle (Bos taurus) genome.

A male linkage map of the cattle (Bos taurus) genome was constructed using nine large half-sib families. The map consists of 269 loci, of which 249 are microsatellites and 20 are structural genes. Among the 249 microsatellites, 140 are markers selected from other maps and 98 are new assignments. Chromosome assignment were established for 35 new markers by somatic cell hybrid analysis, of which 26 were confirmed by linkage analysis. Genome coverage is 1975 cM contained within terminal markers on all 29 autosomes. The average distance between adjacent loci is 9.7 cM, with 72.1% of the map intervals < or = 15 cM and 4.9% of the intervals > or = 25 cM. The inclusion of mapped markers permitted integration and comparisons with other maps, facilitating the identification of discrepancies in chromosome assignment, gene order, and map distance. The inclusion of Type I and blood group markers in the map was useful for comparative mapping, revealing possible blood group orthologies between humans and cattle. The map generated will serve as a useful tool for comparative mapping, mapping of quantitative trait loci and marker assisted selection.

Report of the first workshop on the genetic map of bovine chromosome 1.

A report of the first workshop on the genetic map of bovine chromosome 1 (BTA1) is presented. Five laboratories contributed 31,962 informative meioses from 70 loci. Thirty-two loci which had been typed by at least two laboratories were used to construct a framework genetic map with a likelihood ratio support of at least 1000:1 for locus order. The resulting sex-averaged framework map contained 26 loci and spanned 163.6 CM. The lengths of the female and male maps were 159.5 CM and 165.3 CM, respectively, and there was evidence for an expansion in the telomeric one-third of the male map. Of the four cases where order for closely linked loci differed among the maps produced for each of the contributing laboratories, a consensus order was obtained for three in the framework map. The average genetic distance between framework loci on the sex-averaged map was 6.3 CM.