Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Mar;37(3):509-516.
doi: 10.1007/s10815-020-01702-z. Epub 2020 Feb 5.

Analysis of balanced reciprocal translocations in patients with subfertility using single-molecule optical mapping

Hui Wang  1 , Zhengjun Jia  2 , Aiping Mao  3 , Bing Xu  1 , Shuling Wang  1 , Li Wang  4 , Sai Liu  1   4 , Haiman Zhang  3 , Xiaojie Zhang  3 , Tao Yu  3 , Ting Mu  3 , Mengnan Xu  3 , David S Cram  5 , Yuanqing Yao  6
Affiliations

Analysis of balanced reciprocal translocations in patients with subfertility using single-molecule optical mapping

Hui Wang et al. J Assist Reprod Genet. 2020 Mar.

Abstract

Purpose: Approximately 1% of individuals who carry a balanced reciprocal translocation (BRT) are subfertile. Current karyotyping does not have the resolution to determine whether the breakpoints of the involved chromosomes perturb genes important for fertility. The aim of this study was to apply single-molecule optical mapping (SMOM) to patients presenting for IVF (in vitro fertilization) to ascertain whether the BRT disrupted any genes associated with normal fertility.

Methods: Nine subfertile patients with different BRTs were recruited for the study. Methyltransferase enzyme DLE1 was used to fluorescently label their genomic DNA samples at the recognition motif CTTAAG. The SMOM was performed on the Bionano platform, and long molecules aligned against the reference genome hg19 to identify the breakpoint regions. Mate-pair and PCR-Sanger sequencing were used to confirm the precise breakpoint sequences.

Results: Both breakpoint regions in each of the nine BRTs were finely mapped to small regions of approximately 10 Kb, and their positions were consistent with original cytogenetic banding patterns determined by karyotyping. In three BRTs, breakpoints disrupted genes known to be associated with male infertility, namely NUP155 and FNDC3A [46,XY,t(5;13)(p15;q22)], DPY19L1 [46,XY,t(1;7)(p36.3;p15), and BAI3 [46,XY,t(3;6)(p21;q16)].

Conclusions: The SMOM has potential clinical application as a rapid tool to screen patients with BRTs for underlying genetic causes of infertility and other diseases.

Keywords: Balanced reciprocal translocation (BRT); Infertility; Mate-pair sequencing; Single-molecule optical mapping.

PubMed Disclaimer

Conflict of interest statement

A.M., H.Z., X.Z., T.Y, T.M., M.X., and D.S.C. are employees of Berry Genomics Corporation. None of the authors holds any stocks or bonds in the company. The other authors declare that they have no conflict of interest.

Figures

Fig. 1
Fig. 1
Bionano map showing breakpoint analysis of BRT01 [46,XY,t(5;13)(p15;q22)]. Chromosome 5 and 13 reference maps aligned to the BRT map are shown by arrows. The chromosome and genome map locations identified in the translocation regions are labeled. Coordinates in black are the hg19 locations; those in red are the genome map position for DLE labeling sites
Fig. 2
Fig. 2
Breakpoint validation of BRT01 [46,XY,t(5;13)(p15;q22)]. a Karyogram of chromosomes 5 and 13. Arrows indicate the cytogenetic breakpoints of the translocation chromosomes. b Sanger sequencing. The actual BP positions on chromosomes 5 and 13 are defined. c Genome map showing disruption of two genes FNDC3A and NUP155 as a result of the translocation event. Numbers represent corresponding coordinates from the hg19 reference genome
See this image and copyright information in PMC

References

    1. Ogilvie CM, Braude P, Scriven PN. Successful pregnancy outcomes after preimplantation genetic diagnosis (PGD) for carriers of chromosome translocations. Hum Fertil (Camb) 2001;4(3):168–171. doi: 10.1080/1464727012000199252. - DOI - PubMed
    1. Wilch ES, Morton CC. Historical and clinical perspectives on chromosomal translocations. Adv Exp Med Biol. 2018;1044:1–14. doi: 10.1007/978-981-13-0593-1_1. - DOI - PubMed
    1. Burrow AA, Williams LE, Pierce LC, Wang YH. Over half of breakpoints in gene pairs involved in cancer-specific recurrent translocations are mapped to human chromosomal fragile sites. BMC Genomics. 2009;10:59. doi: 10.1186/1471-2164-10-59. - DOI - PMC - PubMed
    1. Weckselblatt B, Rudd MK. Human structural variation: mechanisms of chromosome rearrangements. Trends Genet. 2015;31(10):587–599. doi: 10.1016/j.tig.2015.05.010. - DOI - PMC - PubMed
    1. Nilsson D, Pettersson M, Gustavsson P, Forster A, Hofmeister W, Wincent J, et al. Whole-genome sequencing of cytogenetically balanced chromosome translocations identifies potentially pathological gene disruptions and highlights the importance of microhomology in the mechanism of formation. Hum Mutat. 2017;38(2):180–192. doi: 10.1002/humu.23146. - DOI - PMC - PubMed