Navarrete-Meneses M P, Ochoa-Mellado I, Gutiérrez-Álvarez R, Martínez-Anaya D, Juárez-Figueroa U, Durán-McKinster C, Lieberman-Hernández E, Yokoyama-Rebollar E, Gómez-Carmona S, Del Castillo-Ruiz V, Pérez-Vera P, Salas-Labadía C
Genetic and cancer Laboratory, National Institute of Pediatrics (Mexico), Mexico City, Mexico.
Genética Humana, Instituto Nacional de Pediatría, Mexico City, Mexico.
Front Genet. 2024 Apr 16;15:1356786. doi: 10.3389/fgene.2024.1356786. eCollection 2024.
The combination of gene content on the marker chromosome, chromosomal origin, level of mosaicism, origin mechanism (chromothripsis), and uniparental disomy can influence the final characterization of sSMCs. Several chromosomal aberrations, including sSMCs, have been observed in 30%-60% of patients with pigmentary mosaicism, and in more than 80%, chromosomal abnormalities are present in the mosaic state. In patients with pigmentary mosaicism the most representative chromosomes involved in sSMCs are 3, 5, 6, 9, 10, 13, 15, 18, 20, and X. In this study, we included the complete clinical, cytogenetic, and molecular characterization of seven patients with pigmentary mosaicism associated with the presence of SMCs of different chromosomal origins.
The patients were diagnosed by the Genetics and Dermatology Department of three different hospitals. Cytogenetic and FISH analyses were performed on peripheral blood, light skin, and dark skin. FISH analysis was performed using different probes, depending on the marker chromosome description. Different array analysis was performed.
To date, of the seven cases studied, the chromosomal origins of six were successfully identified by FISH or array analysis. The chromosomes involved in SMCs were 6, 9, 15, and 18, X. The most frequently found was the centric minute structure.
To date, this group of seven patients constitutes the largest clinical and cytogenetically finely described study of cases with pigmentary mosaicism associated with sSMCs. Undoubtedly, analysis of the two skin types is a fundamental part of our study, as numerical differences may occur in the cell lines found in each skin type. The knowledge generated in this study will help delineate a very heterogeneous entity more accurately, and in the future, analyzing more patients with PM will likely establish a more definite association with the presence of this genetic alteration.
标记染色体上的基因内容、染色体来源、嵌合水平、起源机制（染色体碎裂）以及单亲二体可影响小超数标记染色体（sSMC）的最终特征。在30% - 60%的色素性皮肤镶嵌症患者中观察到包括sSMC在内的几种染色体畸变，且超过80%的患者染色体异常以镶嵌状态存在。在色素性皮肤镶嵌症患者中，参与sSMC的最具代表性的染色体是3、5、6、9、10、13、15、18、20和X染色体。在本研究中，我们纳入了7例与不同染色体来源的sSMC存在相关的色素性皮肤镶嵌症患者的完整临床、细胞遗传学和分子特征分析。
这些患者由三家不同医院的遗传学和皮肤科诊断。对外周血、浅色皮肤和深色皮肤进行细胞遗传学和荧光原位杂交（FISH）分析。根据标记染色体描述，使用不同探针进行FISH分析。进行了不同的阵列分析。
迄今为止，在所研究的7例病例中，通过FISH或阵列分析成功鉴定出6例的染色体来源。参与sSMC的染色体为6、9、15、18、X染色体。最常见的是着丝粒微小结构。
迄今为止，这7例患者组成了关于与sSMC相关的色素性皮肤镶嵌症病例的最大规模临床和细胞遗传学详细描述研究。毫无疑问，对两种皮肤类型的分析是我们研究的一个基本部分，因为在每种皮肤类型中发现的细胞系可能存在数量差异。本研究产生的知识将有助于更准确地描绘一个非常异质的实体，并且在未来，分析更多色素性皮肤镶嵌症患者可能会建立与这种基因改变存在的更明确关联。
