[18号染色体的马赛克复杂结构异常病例的遗传分析]
Minjie Shao1, Zhiqiang Yan, Xiaohui Zhu
1Center for Reproductive Medicine, Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetrics and Gynecology, MOE Key Laboratory for Assisted Reproduction, Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology, Peking University Third Hospital, Beijing 100191, China. yanliyingkind@aliyun.com.
概括
这项研究详细介绍了一种罕见的马赛克主义病例,该病例在不育男性的染色体18上存在复杂的结构异常. 先进的遗传分析揭示了影响精子发育的显著染色体异常.
科学领域:
- 人类遗传学 人类遗传学
- 生殖医学 生殖医学
- 细胞遗传学 细胞遗传学
背景情况:
- 涉及18号染色体复杂结构异常的马赛克主义并不常见.
- 不孕症可能与复杂的染色体异常有关.
研究的目的:
- 确定患有18号染色体马赛克和复杂结构异常的患者的型.
- 为了研究这些异常对游戏生成的影响.
主要方法:
- 在外周血液上进行型定型,复制数变异 (CNV) 分析和光在位杂交 (FISH).
- 单个精子的CNV分析进行,以评估子细胞异常.
主要成果:
- 这位患者呈现出一个复杂的型:mos 47,XY,del(18)(q21q23),+r(18)(q21q23) [84]/46,XY,del(18)(q21q23) [9]/48,XY,del(18)(q21q23),+r(18)(q21q23) ×2[6]/47,XY,del(18)(q21q23),+r(18)(q21q23×2) [1].
- 单个精子分析显示,缺失 (del(18q)) 和重复 (dup(18q)) 的发生率很高,影响了大约33 Mb的染色体18.
结论:
- 18号染色体的复杂结构和数值异常可以发生在正常的表型,这是罕见的.
- 精确的细胞遗传学和分子分析,包括单个精子CNV,对于评估异常胆核类型对性子生成的影响至关重要.
相关概念视频
Karyotyping
60.7K
Overview
60.7K
Meiosis I
193.6K
Meiosis is a carefully orchestrated set of cell divisions, the goal of which—in humans—is to produce haploid sperm or eggs, each containing half the number of chromosomes present in somatic cells elsewhere in the body. Meiosis I is the first such division, and involves several key steps, among them: condensation of replicated chromosomes in diploid cells; the pairing of homologous chromosomes and their exchange of information; and finally, the separation of homologous chromosomes by...
193.6K
Nondisjunction
75.6K
During meiosis, chromosomes occasionally separate improperly. This occurs due to failure of homologous chromosome separation during meiosis I or failed sister chromatid separation during meiosis II. In some species, notably plants, nondisjunction can result in an organism with an entire additional set of chromosomes, which is called polyploidy. In humans, nondisjunction can occur during male or female gametogenesis and the resulting gametes possess one too many or one too few chromosomes.
75.6K
Gene Conversion
9.8K
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
9.8K
Crossing Over
146.9K
Unlike mitosis, meiosis aims for genetic diversity in its creation of haploid gametes. Dividing germ cells first begin this process in prophase I, where each chromosome—replicated in S phase—is now composed of two sister chromatids (identical copies) joined centrally.
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process...
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process...
146.9K
Lampbrush Chromosomes
7.9K
In 1882, Flemming observed lampbrush chromosomes (LBC) in salamander eggs. Later in 1892, Rückert observed LBCs in shark egg cells and coined the term "lampbrush chromosomes" because they looked like brushes used to clean kerosene lamps.
LBCs are made up of two pairs of conjugating homologous chromatids. Each chromatid consists of alternatively positioned regions of condensed-inactive chromatin and loosely placed-active side loops, which can be contracted and extended. The loops...
LBCs are made up of two pairs of conjugating homologous chromatids. Each chromatid consists of alternatively positioned regions of condensed-inactive chromatin and loosely placed-active side loops, which can be contracted and extended. The loops...
7.9K


