Case Report
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Oct 6, 2023; 11(28): 6895-6901
Published online Oct 6, 2023. doi: 10.12998/wjcc.v11.i28.6895
Confusing finding of quantitative fluorescent polymerase chain reaction analysis in invasive prenatal genetic diagnosis: A case report
Cui Chen, Tao Tang, Qi-Ling Song, Yong-Jun He, Yan Cai
Cui Chen, Tao Tang, Qi-Ling Song, Yong-Jun He, Yan Cai, Genetic and Prenatal Diagnosis Center, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, Sichuan Province, China
Author contributions: Chen C and Tang T contributed to manuscript writing and editing and data collection; Song QL and He YJ contributed to image collection; Cai Y contributed to conceptualization and supervision; and all authors have read and approved the final manuscript.
Informed consent statement: Informed written consent was obtained from the patient for the publication of this report and any accompanying images.
Conflict-of-interest statement: The authors declare that they have no conflicts of interest to disclose.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Yan Cai, MD, PhD, Chief Physician, Professor, Genetic and Prenatal Diagnosis Center, Affiliated Hospital of North Sichuan Medical College, No. 1 South Maoyuan Road, Shunqing District, Nanchong 637000, Sichuan Province, China. caiyandd@163.com
Received: June 19, 2023
Peer-review started: June 19, 2023
First decision: August 16, 2023
Revised: August 23, 2023
Accepted: September 14, 2023
Article in press: September 14, 2023
Published online: October 6, 2023
Abstract
BACKGROUND

Quantitative fluorescent polymerase chain reaction (QF-PCR) is a rapid prenatal diagnostic method for abnormalities on chromosomes 21, 18, and 13 and sex chromosomal aneuploidy. However, the value of QF-PCR in diagnosing chromosomal structural abnormalities is limited. In this article, we report a confusing QF-PCR finding in a pregnant woman who underwent amniocentesis.

CASE SUMMARY

The short tandem repeat marker AMXY (Xp22.2/Yp11.2) located on the sex chromosome exhibited a trisomic biallelic pattern, indicating that the karyotype of the fetus might be 47,XYY. Chromosome analysis performed on cultured amniocytes showed a normal male karyotype of the fetus. Copy number variation sequencing confirmed a 500 kb duplication at Yp11.2-Yp11.2 (chrY:6610001_ 7110000) and a 250 kb duplication at Yp11.2-Yp11.2 (chrY:7110001_7360000).

CONCLUSION

In conclusion, the comprehensive application of different methods could achieve a higher detection rate and accuracy for the prenatal diagnosis of chromosomal disorders through chromosomal testing.

Keywords: Quantitative fluorescent polymerase chain reaction, Copy number variation sequencing, Prenatal diagnosis, Partial duplication, Karyotyping, Case report

Core Tip: This case represented an interesting and clinically rare occurrence. The short tandem repeat marker AMXY (Xp22.2/Yp11.2) located on the sex chromosome exhibited a trisomic biallelic pattern in quantitative fluorescent polymerase chain reaction (QF-PCR), indicating the possible existence of two Y chromosomes. However, by analyzing the results of copy number variation sequencing and karyotyping, the fetus was confirmed to have only a partial duplication of the Y chromosome instead of the 47,XYY karyotype. The duplications identified do not include any genes annotated in the Online Mendelian Inheritance in Man database and will not cause the occurrence of birth defects. Therefore, when an abnormality is detected in the QF-PCR data mentioned above, additional methods should be used for comprehensive judgment to avoid misdiagnosis. The strength of the present report is that it provides valuable experience for prenatal diagnosis.