Genetic Basis of Oligozoospermia in Infertile Males

描述(申请人提供)：申请人是一名临床分子遗传学家，有资格获得ABMG认可的临床分子遗传学项目认证。他的长期目标是成为一名独立的内科科学家，专注于研究影响男性生殖健康的男性不育的遗传基础。这项提议将为申请者提供生殖生物学方面的培训以及人类和小鼠遗传学方面的新技术。该项目的总体科学目标是识别和表征导致少精子症(OS)的男性不育相关基因的突变。美国有近400万男性患有男性不育症，其中至少25%被诊断为特发性不育症。男性不育的病因通常与精液特征异常(如精子密度、活力、形态等)有关。少精子症是不育男性中最常见的精液异常。这项研究的具体目标是：1)建立少精子症精液样本的cDNA和DNA集合；2)通过基因直接测序和体外功能分析研究OS相关突变的候选基因；3)利用寡核苷酸微阵列比较基因组杂交(CGH)技术识别和定位与严重OS相关的基因组异常；以及4)使用小鼠基因敲除或敲入模型表征CGH检测到的与OS相关的候选基因。OS相关候选基因的选择将根据它们的蛋白质功能证据和基因在染色体改变区域的位置来优先考虑。申请者将使用cDNA测序方法和全面的全基因组CGH微阵列，研究来自少精子症患者的cDNA和DNA样本中的突变和基因组异常。将开发一种突变的小鼠模型，试图模仿人类最常见的精液异常形式--少精子症。候选人将通过确定基因去除对精子发生和受精的时空影响来描述突变小鼠的特征。识别和鉴定与少精子症相关的特定基因突变将导致新的诊断方法的发展，并将有助于辅助生殖医学的预后。最终，它将提供对男性不育的分子基础的洞察，并最终可能促进非激素避孕药的创造。拟议的研究将在以人类和小鼠遗传学合作研究而闻名的环境中进行。应聘者的长期职业目标是成为一名独立的内科科学家，专注于研究影响男性生殖系统的遗传疾病。

DESCRIPTION (provided by applicant): The applicant is a clinical molecular geneticist who is eligible for ABMG-accredited certification in the Clinical Molecular Genetics program. His long-term objective is to become an independent physician- scientist focused on studying the genetic bases of male infertility that affects the reproductive health of men. This proposal will provide the applicant with training in reproductive biology and new technologies in human and mouse genetics. The overall scientific goal of this project is to identify and characterize mutations in male infertility- associated genes that result in oligozoospermia (OS). Male infertility affects nearly 4,000,000 men in the USA, of which at least 25% are diagnosed as idiopathic. An etiology of male infertility is often associated with abnormal semen characteristics (i.e., sperm concentration, motility, morphology, etc.). Oligozoospermia is the most common semen abnormality observed among infertile males. The Specific Aims of the proposed study are: 1) Develop cDNA and DNA collections of oligozoospermic semen samples; 2) Study candidate genes for OS-associated mutations by direct cDNA sequencing and in vitro functional assays; 3) Identify and map genomic aberrations associated with severe OS, using oligo microarray comparative genome hybridization (CGH) technology; and 4) Characterize the CGH-detected gene-candidate that is associated with OS, using mouse knockout or knock-in models. The selection of OS-associated candidate genes will be prioritized according to their protein functional evidence and the gene's position in altered chromosome region. The applicant will study mutations and genomic abnormalities in cDNA and DNA samples from oligozoospermic patients, using cDNA sequencing approach and comprehensive genome-wide CGH microarray. A mutant mouse model will be developed in attempt to mimic the most common form of semen abnormality, oligozoospermia in human. The candidate will characterize the mutant mice by determining the spatiotemporal effects of gene ablation on spermatogenesis and fertilization. Identification and characterization specific gene mutations that associate with oligozoospermia will lead to the development of novel diagnostic procedures, and will help with prognosis in assisted reproductive medicine. Ultimately, it will provide insight into the molecular basis of male infertility, and eventually may facilitate the creation of non-hormonal contraceptives. Proposed study will be performed in an environment known for its collaborative studies in human and mouse genetics. The long-term career goals of the applicant is to become an independent physician-scientist focused on studying genetic disorders that affect male reproductive system.