{"id":186,"title":"Breakpoint Mapping and Disrupted Gene Identification in Azoospermic Patients With Chromosomal Balanced Translocation by Nanopore Sequencing","title_zh":"纳米孔长读长测序在染色体平衡易位无精子症患者中的断点定位与断裂基因鉴定","url":"https://pubmed.ncbi.nlm.nih.gov/42974818","doi":"10.1002/jcla.70395","pmid":"42974818","journal":"J Clin Lab Anal","kind":"paper","lang":"en","published_at":"2026-11-03T00:00:00+00:00","fetched_at":"2026-11-08T03:43:57+00:00","authors":["Zhang J","Chen XL","Chen JY","Ge YS"],"primary_topic":"male","topics":[{"slug":"male","score":2.0,"hits":["azoospermia","spermatogenesis"]}],"topic_score":2.0,"preference_score":0.0,"preference_labels":[],"llm_score":68.0,"final_score":68.0,"score_dims":{"novelty":72,"rigor":52,"impact":62,"relevance":88,"translation":65},"recommend_reason":"将纳米孔长读长测序用于平衡易位断点的单核苷酸级定位，并首次提出AFF2、MAGI1、FTO断裂与生精障碍相关，方法学与候选基因均具启发性；但样本仅2例、缺乏功能验证与独立队列，结论宜作为假说看待。","keywords":["纳米孔测序","染色体平衡易位","无精子症","断点定位","生精障碍","结构变异"],"selected":1,"story_id":147,"llm_provider":"deepseek","llm_model":"deepseek-flash","llm_effort":"low","source_key":"pubmed-gametes","source_name":"PubMed · 配子与性腺","source_tier":1,"mention_count":1,"has_interpretation":false,"journal_key":null,"journal_tier":"unknown","journal_if":null,"is_mock":false,"summary_zh":"研究纳入2例携带染色体平衡易位的无精子症患者，以G显带核型和染色体微阵列分析（CMA）为参照，采用PromethION平台进行外周血全基因组长读长测序，并借助IGV可视化断点、UCSC进行基因注释。两例平均读长分别为9713.3 bp与8129.8 bp，共鉴定8个断点，其中4个达到单核苷酸分辨率，并发现常规核型分析难以察觉的隐匿性断点。5个断点位于基因间区，未破坏基因完整性；3个断点分别落在AFF2、MAGI1与FTO基因内含子内，导致基因断裂。作者据此提出这三个基因可能是易位相关生精障碍的新候选基因，并认为纳米孔测序是刻画结构变异、挖掘生精相关基因的有力工具。","summary":"OBJECTIVE: To evaluate the utility of nanopore long-read sequencing for precise breakpoint mapping in azoospermia patients with chromosomal balanced translocations, and to elucidate the molecular mechanisms underlying translocation-induced spermatogenic failure. METHODS: Peripheral blood specimens were collected from two azoospermic patients with balanced chromosomal translocations. G-banding karyotype analysis and chromosomal microarray analysis (CMA) results served as the reference standard, and whole-genome long-read sequencing of peripheral blood samples was performed on the PromethION platform. Breakpoint positions were visualized using the Integrative Genomics Viewer (IGV), and gene annotations were conducted using the UCSC Genome Browser. RESULTS: Sequencing was successfully completed for both samples, yielding mean read lengths of 9713.3 bp and 8129.8 bp, respectively. Nanopore sequencing afforded superior molecular resolution of chromosomal aberrations relative to traditional cytogenetic approaches. A total of eight breakpoints were identified through IGV visualization, with four precisely mapped at single-nucleotide resolution. Annotation revealed that five breakpoints resided within intergenic regions without compromising gene integrity, whereas three breakpoints (ChrX:147,998,514-147,998,515, Chr3:65,894,036-65,899,651, and Chr16:53,815,988-53,815,992) were situated within intronic segments of the AFF2, MAGI1, and FTO genes, respectively, resulting in gene disruption. CONCLUSION: This study employed nanopore long-read sequencing to precisely map chromosomal breakpoints in two azoospermic patients, including cryptic breakpoints undetectable by conventional karyotyping. Disruption of AFF2, MAGI1, and FTO at three breakpoints provides novel candidate gene evidence for translocation-associated spermatogenic failure, confirming nanopore sequencing as a robust tool for structural variant characterization and the discovery of spermatogenesis-related genes.","interpretation_basis":null,"fulltext_status":null,"interpretation":null,"fulltext":{"available":false,"status":null,"reason":"尚未抓取全文（未入选、分数未达阈值，或还没跑 fulltext 步骤）","pmcid":null,"license":null,"chars":0,"source":null,"fetched_at":null}}