Abnormal performance of peroral endoscopic myotomy (POEM): a case misdiagnosed as achalasia of cardia.

BACKGROUND: Pseudoachalasia is a rare disease that behaves similarly to achalasia (AC), making it sometimes difficult to differentiate. CASE PRESENTATION: We report a case of 49-year-old male with adenocarcinoma of the gastroesophageal junction misdiagnosed as achalasia. No obvious abnormalities were found in his initial examinations including upper digestive endoscopy, upper gastrointestinal imaging and chest computed tomography (CT). During the subsequent introduced-peroral endoscopic myotomy (POEM), it was found that the mucosal layer and the muscular layer had severe adhesion, which did not receive much attention, delayed the clear diagnosis and effect treatment, and ultimately led to a poor prognosis for the patient. CONCLUSIONS: This case suggests that when patients with AC found mucosal and muscular adhesions during POEM surgery, the possibility should be considered that the lesion may be caused by a malignant lesion.

Short-term outcome of totally minimally invasive versus hybrid minimally invasive Ivor-Lewis esophagectomy.

OBJECTIVES: For resectable esophageal cancer, the choice of total minimally invasive esophagectomy (TMIE) or hybrid minimally invasive esophagectomy (HMIE) remains controversial. The purpose of this study was to evaluate the short-term clinical outcomes of TMIE and HMIE under the Ivor-Lewis procedure. METHODS: The data of 145 patients diagnosed with middle or lower esophageal cancer who underwent radical Ivor-Lewis esophagectomy in the Affiliated Hospital of Qingdao University between January 2018 and December 2019 were retrospectively analyzed. The short-term outcomes such as complications during surgery or within 30 days after surgery and postoperative pain were analyzed. RESULTS: All patients were divided into TMIE group (75 patients) and HMIE group (70 patients). No significant difference was observed in the baseline characteristics of the two groups. TMIE was associated with less blood loss than the HMIE group (p < 0.05). A total of 54 (37.2%) patients had postoperative complications. Although the two groups were statistically similar in the incidence of major complications, patients in the HMIE group were more likely to have pneumonia compared with those in the TMIE group. The numeric rating scale for pain was significantly higher in the HMIE group (p = 0.002) and more patients required an additional opioid analgesia after esophagectomy (p = 0.282). CONCLUSIONS: In conclusion, according to perioperative outcomes, TMIE can benefit patients better than HMIE.

A 1.1 Mb duplication CNV on chromosome 17 contributes to skeletal muscle development in Boer goats.

The Boer goat is one of the top meat breeds in modern animal husbandry and has attracted widespread attention for its unique growth performance. However, the genetic basis of muscle development in the Boer goat remains obscure. In this study, we identified specific structural variants in the Boer goat based on genome-wide selection signals and analyzed the basis of the molecular heredity of related candidate genes in muscle development. A total of 9 959 autosomal copy number variations (CNVs) were identified through selection signal analysis in 127 goat genomes. Specifically, we confirmed that the highest signal CNV (HSV) was a chromosomal arrangement containing an approximately 1.11 Mb (CHIR17: 60062304-61171840 bp) duplicated fragment inserted in reverse orientation and a 5 362 bp deleted region (CHIR17:60145940-60151302 bp) with overlapping genes (e.g., ARHGAP10, NR3C2, EDNRA, PRMT9, and TMEM184C). The homozygous duplicated HSV genotype (+/+) was found in 96% of Boer goats but was not detected in Eurasian goats and was only detected in 4% of indigenous African goats. The expression network of three candidate genes ( ARHGAP10, NR3C2, and EDNRA) regulating dose transcription was constructed by RNA sequencing. Results indicated that these genes were involved in the proliferation and differentiation of skeletal muscle satellite cells (SMSCs) and their overexpression significantly increased the expression of SAA3. The HSV of the Boer goat contributed to superior skeletal muscle growth via the dose effects of overlapping genes.

A Recurrence Predictive Model for Node-negative Esophageal Squamous Cell Carcinoma After Upfront Esophagectomy.

The prognosis for pathologically node-negative (pN0) esophageal squamous cell carcinoma (ESCC) with surgery alone remains poor. We aimed to develop a model for a more precise prediction of recurrence, which will allow personalized management for pN0 ESCC after upfront complete resection. Clinical and pathological records of patients with completely resected pT1-3N0M0 ESCC were retrospectively analyzed between January 2014 and December 2019. A nomogram for the prediction of recurrence was established based on the Cox regression analysis and evaluated by C-index, AUC, and calibration curves. The model was further validated using bootstrap resampling and k-fold cross-validation and compared with the 8th edition of the AJCC TNM staging system using Td-ROC, NRI, IDI, and DCA. Two-hundred-and seventy cases were included in this study. The median follow-up was 45 months. Distant and/or loco-regional recurrences were noted in 89 (33.0%) patients. The predictive model revealed pT-category, differentiation, perineural invasion, examined lymph nodes (ELN), and prognostic nutritional index (PNI) as independent risk factors for recurrence, with a c-index of 0.725 in the bootstrapping cohort. Td-ROC, NRI, and IDI showed a better predictive ability than the AJCC 8th TNM staging system. Based on this model, patients in the low-risk group had a significantly lower recurrence incidence than those in the high-risk group (p < .001). The predictive model developed in this study may facilitate the precise prediction of recurrences for pN0 ESCC after upfront surgery. Stratifying management of those patients might bring significantly better survival benefits.

Development and validation of a nomogram to predict anastomotic leakage after esophagectomy for esophageal carcinoma.

BACKGROUND: This study aimed to identify variables associated with anastomotic leakage after esophagectomy and established a tool for anastomotic leakage prediction. METHODS: Twenty-six preoperative and postoperative variables were retrospectively collected from esophageal cancer patients who were treated with radical esophagectomy from January 2018 to June 2020 in the Affiliated Hospital of Qingdao University. SPSS Version 23.0 and Empower Stats software were used for establishing a nomogram after screening relevant variables by univariate and multivariate Logistic regression analyses. The established nomogram was identified by depicting the receiver operating characteristic (ROC) curves and calibration curve, which was verified by 1,000 bootstrap resamples method. RESULTS: A total of 604 eligible esophageal cancer patients were included, of which 51 (8.4%) patients had anastomotic leakage. Multivariate Logistic regression analysis showed that smoking, anastomotic location, anastomotic technique, prognostic nutritional index (PNI) and ASA score were independent risks of anastomotic leakage. The area under curve (AUC) of ROC in the established nomogram was 0.764 (95% CI, 0.69-0.83). The internal validation confirmed that the nomogram had a great discrimination ability (AUC =0.766). Depicted calibration curve demonstrated a well-fitted prediction and observation probability. In addition, the decision curve analysis concluded that the newly established nomogram is significant for clinical decision-making. CONCLUSIONS: This nomogram provided the individual prediction of anastomotic leakage for esophageal cancer patients after surgery, which might benefit treatment results for patients and clinicians, as well as pre-and postoperative intervention strategy-making.

Autogenous pericardial angioplasty for thymic malignancies: a narrative review.

Locally advanced thymic tumor usually invades adjacent great vessels, while the optimal treatment strategy for vessels resection and prosthetic replacement is still in controversial. We hereby present our series of patients undergoing autologous pericardial angioplasty for thymic malignancies. For invasive thymic tumors involving the superior vena cava (SVC), the replacement vessel was prepared by autologous pericardium and placed between the right atrium and distal left innominate vein stump to establish a SVC bypass. Then, the distal right innominate vein and proximal SVC were blocked, and the thymic tumor and involved vessel were completely resected, followed by SVC reconstruction using pericardium. We retrospectively analyzed the clinical characteristics and short-term outcomes of six related patients with autologous pericardial angioplasty. Due to the homologous advantages of autologous pericardial transplantation, those patients didn't need to receive anticoagulant therapy during the perioperative period, so as to avoid the occurrence of hemorrhage, embolism and other graft-related complications. There were no postoperative long-term thoracic drainage (>7 days), anastomotic bleeding, reconstructed vascular stenosis, embolism or even secondary thoracotomy and other related complications occurred in this case series. The application of autologous pericardium for the replacement of mediastinal great vessels in the surgery of locally advanced thymoma is a safe and effective technique. Compared with former artificial materials, such as polytetrafluoroethylene synthetic prosthesis, autologous pericardial transplantation avoids the occurrence of high risk graft-related complications such as postoperative hemorrhage and vascular stenosis, and its clinical application prospect is worth expecting.

Role of radiation therapy in node-negative esophageal cancer: A propensity-matched analysis.

BACKGROUND: This study investigated the prognostic impact of (neo-)adjuvant radiation therapies in early stage esophageal cancer. METHODS: A retrospective analysis using the Surveillance, Epidemiology, and End Results (SEER) database was conducted from 2004 to 2016. Patients with pathologically staged T1-4N0M0 esophageal cancer were divided into two treatment groups: (i) neoadjuvant radiotherapy followed by surgery; and (ii) upfront esophagectomy followed by adjuvant radiotherapy. Propensity scored match and Cox proportional hazards model were used to identify covariates associated with overall survival and cancer-specific survival. RESULTS: There were 821 patients selected, of whom 588 (71.6%) received neoadjuvant radiotherapy and 233 (28.4%) received adjuvant radiotherapy. For the entire cohort, neoadjuvant radiotherapy was associated with a significantly benefit in five-year survival outcomes compared with adjuvant radiotherapy (P < 0.01). After matching, the survival outcomes were still better for neoadjuvant radiotherapy than that of adjuvant treatment. Stratifying based on pathologic tumor status, neoadjuvant radiation was associated with improved CSS (five-year survival 73.7% vs. 42.1%; P = 0.014) for localized (pT3-4N0) disease. The Cox multivariate regression analysis revealed that the addition of neoadjuvant radiation for pT3-4N0 diseases with tumor length ≥ 5 cm and squamous cell carcinoma, was a powerful prognostic factor for improved cancer-specific survival (P < 0.01). CONCLUSIONS: Compared with adjuvant radiotherapy, the addition of neoadjuvant radiation for pT3-4N0 diseases has been associated with improved cancer-specific survival in high-risk patients. Studies on preoperative neoadjuvant therapies would be plausible in high-risk esophageal cancer patients.

Neoadjuvant chemoradiotherapy plus surgery versus surgery alone for clinical node-negative esophageal carcinoma.

BACKGROUND: The impact of neoadjuvant chemoradiotherapy (nCRT) on early stage esophageal cancer is unknown. Here, we compared the outcomes after esophagectomy alone or nCRT plus surgery for clinically staged node-negative esophageal cancer. METHODS: We searched the Surveillance, Epidemiology, and End Results database for patients with clinically node-negative (cN0) esophageal cancer from 2004 to 2016 who underwent surgery alone or nCRT plus surgery. Propensity score matching and Cox regression analysis were used to identify covariates associated with overall survival and cancer-specific survival. RESULTS: A total of 1587 patients were retrospectively identified, of whom 49.8% (n = 791) received nCRT and 80.2% (n = 1273) were truly node-negative diseases. For the entire cohort, surgery alone was associated with a statistically significant but modest absolute increase in survival outcomes (P < 0.01). After matching, nCRT was associated with improved five-year overall survival for pT3-4N0 (localized) disease (59.6% vs. 37.7%; P < 0.001) and pathological node-positive disease (60.5% vs. 40.7%; P = 0.002). Cox multivariate regression analysis revealed that the addition of nCRT for truly node-negative patients with tumor length ≥ 3 cm, pT1-2N0 (early-staged) and localized disease were independent risk factors for survival than surgery alone (P < 0.01). CONCLUSIONS: Compared with surgery alone, patients with cN0 esophageal cancer with pathological node-positive or localized true node-negative disease gain a significant survival benefit from nCRT. However, nCRT plus surgery was associated with decreased survival for early-staged true node-negative patients. This finding may have significant implications on the use of neoadjuvant chemoradiation in patients with cN0 disease.

Development and validation of a nomogram prognostic model for patients with neuroendocrine tumors of the thymus.

BACKGROUND: The purpose of this study was to analyze the clinical characteristics and prognostic survival of patients with neuroendocrine tumors of the thymus (NETTs), and to develop and validate a nomogram model for predicting the prognosis of patients. METHODS: We conducted a retrospective analysis of patients with neuroendocrine tumors of the thymus in the Surveillance, Epidemiology, and End Results (SEER) database in the United States between 1988 and 2016. Cox scale risk regression analysis, the Kaplan-Meier method and log-rank test were used to carry out the significance test to determine the independent prognostic factors, from which a nomogram for NETTs was established. C-index and calibration curve were used to evaluate the prediction accuracy of the model. External validation of the nomogram was performed using data from our center. RESULTS: A total of 254 patients with NETTs were collected in the SEER database. In the multivariable analysis, T stage, tumor grade, surgery, and chemotherapy were found to be independent factors affecting the prognosis of patients (all P < 0.05). A nomogram model was constructed based on these variables, and its c-index was 0.707 (0.661-0.752). The c-index results showed that the nomogram model had better authentication capability than the eighth edition of the tumor, node, metastasis (TNM) staging system and Masaoka-Koga (MK) staging system. The calibration curve showed that the model could accurately predict patient prognosis. CONCLUSIONS: The study established a nomogram model that predicted the overall survival rate of one-, three- and five-years, and used the survival prediction model to optimize individualized therapy and prognostic follow-up through risk stratification.

Totally mechanical linear stapled anastomosis for minimally invasive Ivor Lewis esophagectomy: Operative technique and short-term outcomes.

BACKGROUND: Anastomosis is one of the important factors affecting anastomotic complications after esophagectomy, and multiple reports have compared anastomotic complications among various techniques. However, there is insufficient evidence in the literature to definitively recommend one anastomotic technique over another. METHOD: We retrospectively evaluated 34 consecutive patients who underwent an improved totally mechanical side-to-side: posterior-to-posterior linear stapled (TM-STS) technique for minimally invasive Ivor Lewis esophagogastric anastomosis, performed by a single surgeon between February 2015 to November 2017. The operative techniques and short-term outcomes are analyzed in this study. RESULTS: There were no conversions to an open approach and a complete resection was achieved in all patients undergoing this improved procedure. During the first half of the series, the median operation time was 355 minutes, ranging from 257 to 480 minutes. Over the second half of this series, the median operation time was reduced to 256 minutes. There were no mortalities or serious postoperative complications. Only one patient (2.9%) had an anastomotic leak, which resolved without intervention. Another patient (2.9%) experienced transient, delayed conduit emptying which upper gastrointestinal radiography determined was due to a mechanical obstruction caused by an abnormally long gastric tube in the chest cavity. CONCLUSIONS: The results of our study suggest that this improved TM-STS technique is safe and effective for minimally invasive Ivor Lewis esophagectomy, and can be considered as one of the alternative procedure for patients with lower esophageal as well as Siewert types I/II gastroesophageal junction carcinoma.

Identification of a Goat Intersexuality-Associated Novel Variant Through Genome-Wide Resequencing and Hi-C.

Background: Polled intersex syndrome (PIS) leads to reproductive disorders in goats and exerts a heavy influence on goat breeding. Since 2001, the core variant of an 11.7 kb deletion at ~129 Mb on chromosome 1 (CHI1) has been widely used as a genetic diagnostic criterion. In 2020, a ~0.48 Mb insertion within the PIS deletion was identified by sequencing in XX intersex goats. However, the suitability of this variation for the diagnosis of intersex goats worldwide and its further molecular genetic mechanism need to be clarified. Results: The whole-genome selective sweep of intersex goats from China was performed with whole-genome next-generation sequencing technology for large sample populations and a case-control study on interbreeds. A series of candidate genes related to the goat intersexuality phenotype were found. We further confirmed that a ~0.48 Mb duplicated fragment (including ERG and KCNJ15) downstream of the ~20 Mb PIS region was reversely inserted into the PIS locus in intersex Chinese goats and was consistent with that in European Saanen and Valais black-necked goats. High-throughput chromosome conformation capture (Hi-C) technology was then used to compare the 3D structures of the PIS variant neighborhood in CHI1 between intersex and non-intersex goats. A newly found structure was validated as an intrachromosomal rearrangement. This inserted duplication changed the original spatial structure of goat CHI1 and caused the appearance of several specific loop structures in the adjacent ~20 kb downstream region of FOXL2. Conclusions: Results suggested that the novel complex PIS variant genome was sufficient as a broad-spectrum clinical diagnostic marker of XX intersexuality in goats from Europe and China. A series of private dense loop structures caused by segment insertion into the PIS deletion might affect the expression of FOXL2 or other neighboring novel candidate genes. However, these structures require further in-depth molecular biological experimental verification. In general, this study provided new insights for future research on the molecular genetic mechanism underlying female-to-male sex reversal in goats.

Adjuvant radiotherapy for patients with pathologic node-negative esophageal carcinoma: A population based propensity matching analysis.

BACKGROUND: The impact of adjuvant treatment for esophageal carcinoma with tumor-negative lymph nodes after upfront radical esophagectomy is still uncertain. This study investigated the effects of postoperative radiotherapy in pT1-3N0 esophageal carcinoma after radical resection. METHOD: We retrospectively identified pT1-3N0M0 esophageal carcinoma patients between 2000 and 2016 from the Surveillance, Epidemiology, and End Results database. Patients with upfront esophagectomy were categorized as having received surgery alone (SA) and surgical resection followed by adjuvant radiotherapy (SA + RT). Propensity score matching, univariate and multivariate analysis were performed to compare overall survival (OS) and cause-specific survival (CSS). RESULTS: A total of 2862 patients were identified, of whom 274 received SA + RT and 2588 received SA. The median follow-up was 60.4 months (95%CI, 58.7-62.1 months). The five-year OS and CSS were better for SA group compared with SA + RT group (P < 0.001, respectively). Furthermore, after matching, the OS and CSS were still significantly better for SA patients. For T subgroup analysis, postoperative radiotherapy was an independent prognostic factor only for pT1 patients with worse OS, without survival differences for pT2 and pT3 patients. However, after multivariate cox analysis, postoperative radiotherapy can provide significantly better OS for pT3 patients with tumor length ≥5 cm (P = 0.03; 95%CI, 0.29-0.94). CONCLUSIONS: Among pT1-3N0M0 esophageal carcinoma patients, postoperative radiotherapy can provide significantly better OS for pT3 patients with tumor length ≥5 cm. However, there are no survival benefits for pT1-2 patients after SA + RT procedure. This finding may have significant implications on the use of adjuvant radiation in patients with pN0 disease.

Video-Assisted Vs Thoracotomy Sleeve Lobectomy for Lung Cancer: A Propensity Matched Analysis.

BACKGROUND: In this retrospective study, we evaluated the safety and efficacy of video-assisted thoracic surgery (VATS) sleeve lobectomy for patients with centrally located non-small cell lung cancer. METHODS: All consecutive patients who received VATS sleeve lobectomy (n = 54) and thoracotomy sleeve lobectomy (n = 94) were analyzed retrospectively; after propensity score matching, 78 paired cases were selected for further statistical analysis. RESULTS: Among all patients, the VATS group showed significantly better recurrence-free survival and overall survival than the thoracotomy group (P = .025 and P = .026, respectively) with smaller total tumor size and earlier pathological tumor-node-metastasis (TNM) stage. Nevertheless, after matching, the recurrence-free survival (50.9% vs 48.7%; P = .445) and overall survival (79.5% vs 66.7%; P = .198) were not significantly different. There was significantly less blood loss (228 vs 246 mL; P = .022), shorter thoracic drainage stay (4.6 vs 6.8 days; P < .001), and postoperative hospital stay (9.2 vs 11.3 days; P = .033) in the VATS group. Multivariate Cox analyses demonstrated that the surgical procedure was not an independent prognostic factor for recurrence-free survival, not only for patients with an invasive component size of 3 cm or less and negative lymphatic invasion, but for locally advanced patients with an invasive tumor size >3 cm (hazard ratio: 0.94; 95% confidence interval: 0.36-2.45; P = .55) or positive lymphatic invasion (hazard ratio: 0.91; 95% confidence interval: 0.35-2.39; P = .41). CONCLUSIONS: VATS sleeve lobectomy is a safe and effective procedure associated with better postoperative recovery and equivalent oncological results, even for locally advanced non-small cell lung cancer patients with an invasive tumor size larger than 3 cm or accompanying lymphatic invasion.

A tension tracheal diverticulum: recurrence after interventional sclerotherapy followed by transcervical resection.

Tracheal diverticulum is a rarely congenital or acquired tracheal benign entity, characterized by round or spherical out-pouching of the tracheal wall. Most of the tracheal diverticula are asymptomatic disease, and therefore surgical treatment has not been widely reported. Symptomatic diverticula can accept conservative treatment such as anti-inflammatory, postural drainage, etc. Transcervical resection or endoscopic laser surgery or electrosurgery should be considered for patients with severe symptoms or combined with repeated tracheobronchial inflammation. However, there is still insufficient evidence to recommend the optimal therapeutic schedule at present. We describe a special tension tracheal diverticulum with rare symptoms of dysphagia and dizziness for the first time which has a recurrence after interventional sclerotherapy followed by transcervical resection.

Genetic diversity of the Chinese goat in the littoral zone of the Yangtze River as assessed by microsatellite and mtDNA.

The objective of this study was to assess the genetic diversity and population structure of goats in the Yangtze River region using microsatellite and mtDNA to better understand the current status of those goat genetic diversity and the effects of natural landscape in fashion of domestic animal genetic diversity. The genetic variability of 16 goat populations in the littoral zone of the Yangtze River was estimated using 21 autosomal microsatellites, which revealed high diversity and genetic population clustering with a dispersed geographical distribution. A phylogenetic analysis of the mitochondrial D-loop region (482 bp) was conducted in 494 goats from the Yangtze River region. In total, 117 SNPs were reconstructed, and 173 haplotypes were identified, 94.5% of which belonged to lineages A and B. Lineages C, D, and G had lower frequencies (5.2%), and lineage F haplotypes were undetected. Several high-frequency haplotypes were shared by different ecogeographically distributed populations, and the close phylogenetic relationships among certain low-frequency haplotypes indicated the historical exchange of genetic material among these populations. In particular, the lineage G haplotype suggests that some west Asian goat genetic material may have been transferred to China via Muslim migration.

Associations between abnormal vitamin D metabolism pathway function and non-small cell lung cancer.

Lung cancer is a type of malignant tumor derived from the respiratory system, which is the leading cause of cancer-associated mortality worldwide, of which ~80% of cases are attributable to non-small cell lung cancer (NSCLC). A previous study demonstrated that 1α,25-Dihydroxyvitamin D3 (1α,25(OH)2D3), derived from the vitamin D metabolic pathway contributes an antitumor effect. Aberrant expression of the essential enzyme encoding genes, Cytochrome P450 Family 27 Subfamily A Member 1 (CYP27A1), Cytochrome P450 Family 27 Subfamily B Member 1 (CYP27B1), and Cytochrome P450 Family 24 Subfamily A Member 1 (CYP24A1) may be associated with lung cancer. However, a lack of evidence exists concerning the association between CYP27A1, CYP27B1, CYP24A1 expression and NSCLC. The aim of the present study was to investigate the functions of CYP27A1, CYP27B1 and CYP24A1 expression in NSCLC. Lung cancer tissue and para-carcinoma control tissue were collected from patients with NSCLC. Reverse transcription-quantitative polymerase chain reaction was applied to analyze CYP27A1, CYP27B1 and CYP24A1 mRNA expression in lung cancer tissues. An association analysis was performed between the aforementioned metabolic enzymes and patients with NSCLC age, gender, tumor node metastasis (TNM) stage, pathological type, differentiation and prognosis. CYP27B1 and CYP24A1 mRNA were upregulated in NSCLC compared with controls (P<0.05). However, no significant differences in CYP27A1 expression were observed between NSCLC and control. In addition, CYP24A1 expression was not associated with age, sex, smoking or TNM stage, but was associated with pathological type, differentiation and prognosis (P<0.05). CYP27B1 expression was significantly associated with TNM stage, differentiation, and prognosis, but not age, sex, smoking or pathological type. In conclusion, CYP27B1 and CYP24A1 may be considered as independent prognostic factors of NSCLC and may be novel therapeutic targets to assist clinical diagnosis, treatment and prognosis of the disease.

Conservation genetics in Chinese sheep: diversity of fourteen indigenous sheep (Ovis aries) using microsatellite markers.

The domestic sheep (Ovis aries) has been an economically and culturally important farm animal species since its domestication around the world. A wide array of sheep breeds with abundant phenotypic diversity exists including domestication and selection as well as the indigenous breeds may harbor specific features as a result of adaptation to their environment. The objective of this study was to investigate the population structure of indigenous sheep in a large geographic location of the Chinese mainland. Six microsatellites were genotyped for 611 individuals from 14 populations. The mean number of alleles (±SD) ranged from 7.00 ± 3.69 in Gangba sheep to 10.50 ± 4.23 in Tibetan sheep. The observed heterozygote frequency (±SD) within a population ranged from 0.58 ± 0.03 in Gangba sheep to 0.71 ± 0.03 in Zazakh sheep and Minxian black fur sheep. In addition, there was a low pairwise difference among the Minxian black fur sheep, Mongolian sheep, Gansu alpine merino, and Lanzhou fat-tailed sheep. Bayesian analysis with the program STRUCTURE showed support for 3 clusters, revealing a vague genetic clustering pattern with geographic location. The results of the current study inferred high genetic diversity within these native sheep in the Chinese mainland.

Complete mitochondrial genome of Hechuan white goat in China (Capra hircus).

The Hechuan white goat (Capra hircus), an indigenous of China. Here, we describe the complete mitochondrial genome sequence of Hechuan white goat. The mitogenome is 16,640 nt in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and a control region. As in other mammals, most mitochondrial genes are encoded on the heavy strand, except for ND6 and eight tRNA genes, which are encoded on the light strand. Its overall base composition is A: 33.5%, T: 27.3%, C: 26.1% and G: 13.1%. The complete mitogenome of the local subspecies of Hechuan white goat could provide an important data to further explore the breed improvement in Chinese goat.

A complete mitochondrial genome of Youzhou black-skin goat.

The Youzhou black-skin goat (Capra hircus), an indigenous breed of Chinese southwest. Here, we describe the complete mitochondrial genome sequence of Hechuan white goat. The mitogenome is 16,640 nt in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and a control region. As in other mammals, most mitochondrial genes are encoded on the heavy strand, except for ND6 and eight tRNA genes, which are encoded on the light strand. Its overall base composition is A: 33.5%, T: 27.3%, C: 26.1% and G: 13.1%. The complete mitogenome of the local subspecies of Hechuan white goat could provide an important data to further breed improvement and animal genetics resource conservation in China.