Background Although Chromosomal microarray analysis (CMA) is a powerful diagnostic technology for detecting chromosomal copy number variants (CNVs), it detects numerous variants of unknown significance (VUSs), which poses a great challenge for genetic counselling. Terminal deletion of the long arm of chromosome 4 is a rare genetic aberration. Few cases of interstitial deletion sharing the common deleted segment have been reported. Case presentation A male foetus with a 7.22-Mb deletion at chromosome 4q32.2q32.3 was found in the proband. The paternal genotype was normal. His asymptomatic mother with a normal phenotype and intelligence was found to carry the same deletion at the long arm of chromosome 4. The clinical significance of arr[GRCh37] 4q32.2q32.3(162858958_170081268)×1 remains uncertain. To the best of our knowledge, this is the first case report on a VUS of 4q32 deletion and the second report of a heterochromatic CNV involving part of the long arm of chromosome 4 in a phenotypically normal mother and child. The identification of this case contributes to additional understanding of deletion at 4q32.2q32.3. This report may provide a reference for prenatal diagnosis and genetic counselling in patients who have genotypes of similar cytogenetic abnormalities. Conclusions The novel 7.22-Mb deletion at chromosome 4q32.2q32.3 (162858958-170081268) is a VUS. The foetus inherited this VUS from a phenotypically normal mother.

中文翻译：

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通过 SNP 阵列对染色体 4q32.2q32.3 处母体 7.22-Mb 缺失的产前诊断。

背景 虽然染色体微阵列分析（CMA）是一种检测染色体拷贝数变异（CNVs）的强大诊断技术，但它检测出大量未知意义的变异体（VUSs），这对遗传咨询提出了很大的挑战。4号染色体长臂末端缺失是一种罕见的遗传异常。据报道，很少有共享共同删除段的间隙删除案例。病例介绍 在先证者中发现了一个在染色体 4q32.2q32.3 处有 7.22-Mb 缺失的男性胎儿。父系基因型正常。他的无症状母亲具有正常的表型和智力，被发现在 4 号染色体的长臂上携带相同的缺失。arr[GRCh37] 4q32.2q32.3(162858958_170081268)×1 的临床意义仍不确定。据我们所知，这是第一个关于 4q32 缺失的 VUS 病例报告和第二个关于表型正常的母亲和孩子中涉及 4 号染色体长臂部分的异染色性 CNV 的报告。该病例的鉴定有助于进一步了解 4q32.2q32.3 的缺失。本报告可为具有相似细胞遗传学异常基因型患者的产前诊断和遗传咨询提供参考。结论 染色体 4q32.2q32.3 (162858958-170081268) 上的新型 7.22-Mb 缺失是一种 VUS。胎儿从表型正常的母亲那里继承了这种 VUS。该病例的鉴定有助于进一步了解 4q32.2q32.3 的缺失。本报告可为具有相似细胞遗传学异常基因型患者的产前诊断和遗传咨询提供参考。结论 染色体 4q32.2q32.3 (162858958-170081268) 上的新型 7.22-Mb 缺失是一种 VUS。胎儿从表型正常的母亲那里继承了这种 VUS。该病例的鉴定有助于进一步了解 4q32.2q32.3 的缺失。本报告可为具有相似细胞遗传学异常基因型患者的产前诊断和遗传咨询提供参考。结论 染色体 4q32.2q32.3 (162858958-170081268) 上的新型 7.22-Mb 缺失是一种 VUS。胎儿从表型正常的母亲那里继承了这种 VUS。