Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric & Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science & Peking Union Medical College, Beijing, China.
BMC Med Genomics. 2024 Aug 29;17(1):222. doi: 10.1186/s12920-024-01987-4.
Kagami-Ogata syndrome (KOS) and Temple syndrome (TS) are two imprinting disorders characterized by the absence or reduced expression of maternal or paternal genes in the chromosome 14q32 region, respectively. We present a rare prenatally diagnosed case of recurrent KOS inherited from a mother affected by TS.
The woman's two affected pregnancies exhibited recurrent manifestations of prenatal overgrowth, polyhydramnios, and omphalocele, as well as a small bell-shaped thorax with coat-hanger ribs postnatally. Prenatal genetic testing using a single-nucleotide polymorphism array detected a 268.2-kb deletion in the chromosome 14q32 imprinted region inherited from the mother, leading to the diagnosis of KOS. Additionally, the woman carried a de novo deletion in the paternal chromosome 14q32 imprinted region and presented with short stature and small hands and feet, indicating a diagnosis of TS.
Given the rarity of KOS as an imprinting disorder, accurate prenatal diagnosis of this rare imprinting disorder depends on two factors: (1) increasing clinician recognition of the clinical phenotype and related genetic mechanism, and (2) emphasizing the importance of imprinted regions in the CMA workflow for laboratory analysis.
Kagami-Ogata 综合征(KOS)和 Temple 综合征(TS)是两种印记疾病,分别表现为 14q32 染色体区域母源或父源基因的缺失或表达减少。我们报告了一例罕见的产前诊断的 KOS 病例,该病例是由患有 TS 的母亲遗传而来。
该女性的两次受累妊娠均表现出产前过度生长、羊水过多和脐膨出的反复表现,以及出生后呈小钟形胸廓伴衣架状肋骨。使用单核苷酸多态性微阵列进行的产前基因检测发现,从母亲遗传而来的 14q32 染色体印记区域存在 268.2kb 的缺失,导致 KOS 的诊断。此外,该女性还携带父源 14q32 印记区域的新发缺失,并表现为身材矮小、手脚小,提示 TS 的诊断。
鉴于 KOS 作为一种印记疾病的罕见性,对这种罕见的印记疾病进行准确的产前诊断取决于两个因素:(1)提高临床医生对临床表型和相关遗传机制的认识,(2)强调印记区域在 CMA 工作流程中的重要性,以便进行实验室分析。