Prenatal diagnosis of a de novo tetrasomy 15q24.3‐25.3: Case report and literature review

Abstract

Background Terminal duplication on chromosome 15q is a rare chromosomal variation. Affected individuals show similar features such as growth dysplasia or the development of frontal bossing, body deformities, facial abnormalities, and genitourinary or cardiovascular disorders. However, it is not yet clear whether such 15q repeats lead to identifiable patterns of clinical abnormalities. Therefore, the purpose of this study was to analyze the prenatal diagnostic results and clinical manifestations of a fetus with 15q duplication and to summarize the literature. Methods The case was a fetus at 28 weeks of gestation. The risk of Down syndrome from second‐trimester screening was 1/140. Prenatal ultrasound and amniocentesis were performed, and chromosomal microarray analysis (CMA) was used for genetic analysis. Results The fetus had abnormal clinical features, including intracardiac echogenic focus in the left ventricle, an aberrant right subclavian artery, and growth delay. The fetal chromosomal karyotype was 46,XX,15q?,12q?,21pstk+, and CMA revealed a 10.163 Mb duplication at 15q24.3‐q25.3. The couple chose to terminate the pregnancy after careful consideration. Conclusions The combination and rational application of cytogenetics technology and molecular genetics technology such as CMA will open up the field of clinical application and provide useful genetic counseling for parents of fetuses carrying such chromosomal duplications.

Novel autopsy and genetic findings in an acardiac twin: case report and literature review

“…The features described in individual cases are sometimes opposing, such as overgrowth and growth restriction. 41 - 44 Given the aforementioned range of abnormalities, it is not surprising that a number of morbid genes are present at 15q25.1, with an associated broad array of functions and disease correlates. 41 Copy number losses involving the proximal region of 6q are also rare.…”

“… 41 - 44 Given the aforementioned range of abnormalities, it is not surprising that a number of morbid genes are present at 15q25.1, with an associated broad array of functions and disease correlates. 41 Copy number losses involving the proximal region of 6q are also rare. A review of 12 cases by Hopkin et al 45 found that deletions involving 6q11 - 6q16 are commonly associated with hernias, upslanting palpebral fissures, and thin lips.…”

The Application of Optical Genome Mapping (OGM) in Severe Short Stature Caused by Duplication of 15q14q21.3

“…The features of chromosome 15q11-q13 duplication syndrome (OMIM 608636), which has been implicated in Angelman syndrome and Prader-Willi syndrome, include autism, mental retardation, ataxia, seizures, developmental delays, and behavioral problem. Many investigators have also reported several patients carrying duplication of the distal long arm in chromosome 15 [29][30][31], which manifests primarily as frontal bossing, short palpebral fissures, long philtrum, lowset ears, high-arched palate, retrognathia, arachnodactyly, microcephaly, joint contractures, and development delay. However, patients with duplication in the medial long arm of chr 15 are rare [32][33][34].…”