MUTATIONS INDUCED IN HUMAN SPERM BY CANCER THERAPY

描述：(申请人描述) 放化疗对小鼠生殖细胞的致突变作用 并在它们的后代中引起遗传病。然而，在人类中， 对这些疗法的诱变效果的评估是有限的。 由于突变频率低，后代数量少，且数量有限 对后代的跟踪调查。为了克服这些困难，基因变化在 高度可变的DNA重复基因座(小卫星和微卫星)直接在 受辐射或辐射的男性的单个精子细胞的DNA 化疗药物将被测量。高效的DNA检测 通过一种新的方法，单个细胞的序列突变现在成为可能 被称为小池聚合酶链式反应(SP-PCR)。DNA从最高到 通过聚合酶链式反应在重复基因座扩增100个精子，并在一条通道上通过 电泳，并分析代表单个突变体的条带 精子。在一次实验和突变中可以筛选数以千计的精子 低至0.2%的频率可以被准确地确定。 这项初步研究的目的是检验DNA重复的假设 人类的基因座对重复数的诱导非常敏感 由基因毒剂引起的突变。精子中的突变频率将是 SP-PCR法测定。将采用纵向研究设计。精液 样本会在放射或化疗后从病人身上取得，而 突变频率将与治疗前进行比较。 如果在治疗后观察到海拔，将会有额外的样本 以确定突变频率是否发生变化 随着时间的推移。 研究人群包括患有霍奇金氏病、精原细胞瘤和 接受烷化或非烷化药物治疗的慢性粒细胞白血病 化疗或放射治疗。突变分析将在 小卫星M5205、M532和CEB1基因座及其微卫星 三核苷酸重复与强直性肌营养不良和亨廷顿病相关 疾病基因和雄激素受体基因。 结果将被用来比较不同种类的 癌症治疗方案，并确定突变效应是否 随着时间的推移而持续或下降；最终这些数据可用于 致突变风险的评估。这些信息将非常有价值 为癌症治疗的长期幸存者提供生殖咨询。

DESCRIPTION: (Applicant's Description) Radiation and chemotherapy are mutagenic towards germ cells of experimental animals and cause genetic disease in their offspring. However, in humans the assessment of the mutagenic effects of these therapies has been limited by the low frequency of mutations, small numbers of offspring, and limited follow-up of offspring. To overcome such difficulties, genetic changes at the highly mutable DNA repeat loci (mini- and microsatellites) directly in the DNA of individual sperm cells from men exposed to radiation or chemotherapeutic drugs will be measured. Efficient detection of DNA sequence mutations in individual cells is now possible with a novel method called the small-pool polymerase chain reaction (SP-PCR). DNA from up to 100 sperm is amplified at a repeat locus by PCR, separated in one lane by electrophoresis, and analyzed for bands representing individual mutant sperm. Thousands of sperm can be screened in one experiment and mutation frequencies as low as 0.2 percent can be accurately determined. The objective of this pilot study is to test the hypothesis that DNA repeat loci in humans are very sensitive to the induction of repeat number mutations by genotoxic agents. The mutation frequencies in sperm will be measured by SP-PCR. A longitudinal study design will be employed. Semen samples will be obtained from patients after radio or chemotherapy, and the mutation frequencies will be compared with those obtained before treatment. If elevations are observed after therapy, additional samples will be obtained to determine whether there are changes in the mutation frequency with time. The study population includes men with Hodgkin's disease, seminoma, and chronic myelogenous leukemia who receive alkylating or non-alkylating agent chemotherapy or radiotherapy. Mutation analysis will be performed at the mini-satellite M5205, M532, and CEB1 loci and at the microsatellite trinucleotide repeats associated with the myotonic dystrophy and Huntington disease loci and the androgen receptor gene. The results will be used to compare the mutagenic potentials of different cancer treatment regimens and determine whether the mutagenic effects are persistent or decline with time; eventually these data may be used for estimation of mutagenic risks. This information would be extremely valuable in the reproductive counseling of long-term survivors of cancer therapy.