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Molecular Biology Reports

, Volume 47, Issue 2, pp 1513–1520 | Cite as

Spliceogenic analysis of BRCA1 c.439T>C (rs794727800) variant by High Resolution Melting Analysis

  • Angelo MinucciEmail author
  • Giorgia Mazzuccato
  • Marco D’Indinosante
  • Lucia Di Nardo
  • Paola Concolino
  • Maria De Bonis
  • Andrea Urbani
  • Giovanni Scambia
  • Anna Fagotti
  • Ettore Capoluongo
Short Communication
  • 69 Downloads

Abstract

Correct classification of genomic variants causing potentially aberrant splicing is of utmost importance for patient management, especially in clinically actionable genes such as BRCA1/2. In this article, we report molecular evaluation of the BRCA1 c.439T>C (rs794727800, p.Leu147=) variant based on RNA of a patient suffering with high-grade serous ovarian cancer syndrome, to add new evidence to the only in silico data available for this variant. High Resolution Melting Analysis (HRMA) was used for the first time to investigate the spliceogenicity of a BRCA1 variant. HRMA with Sanger sequencing provided evidence that the c.439C allele does not cause aberrant splicing of the BRCA1 exon 7. In addition, HRMA with Sanger highlighted a different expression of the naturally occurring BRCA1 r.442_444del (c.442_444delCAG, p.Gln148del, at DNA level) isoform between blood and tumor, in this patient. HRMA is an alternative molecular approach to analyze spliceogenic properties of the c.439T>C variant and potentially for all those BRCA1/2 variants affecting splicing sites. These new evidences allowed to classify definitively the c.439T>C variant as benign. Furthermore, the different BRCA1 r.442_444del expression opens the discussion to consider a wider classification criteria for the splicing variants, including molecular evaluation at tissue level, which is an aspect currently scarcely considered in BRCA1/2 variant classification recommendations.

Keywords

Spliceogenic analysis BRCA1/2 genes High Resolution Melting Analysis BRCA1 c.439T>C variant BRCA1 r.442_444del isoform 

Abbreviations

HBOC

Hereditary breast and/or ovarian cancer

PVs

Pathogenic variants

BRCA

BRCA1/2

PARP-1

Poly (ADP-ribose) polymerase

VUS

Variants of unknown significance

ENIGMA

Evidence-based network for the interpretation of germline mutant alleles

MAF

Minor allele frequency

HGSOC

High grade serous ovarian cancer

HRMA

High-resolution melting analysis

FIGO

International federation of gynecologists and obstetricians

FT

Fresh tissue

NGS

Next generation sequencing

VAF

Variant allele frequency

Notes

Acknowledgement

We would like to thank Franziska M. Lohmeyer for her critical review and English revision.

Compliance with ethical standards

Conflict of interest

The authors declared no potential conflicts of interest.

Ethical approval

This study complied with the Ethical Principles for Medical Research Involving Human Subjects according to the World Medical Association Declaration of Helsinki and was certified by the Committee of the Applicable Institution of the Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome.

Informed consent

Informed consent was taken from all participants.

Supplementary material

11033_2019_5199_MOESM1_ESM.docx (836 kb)
Supplementary material 1 (DOCX 836 kb)

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Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  • Angelo Minucci
    • 1
    Email author
  • Giorgia Mazzuccato
    • 1
  • Marco D’Indinosante
    • 2
  • Lucia Di Nardo
    • 3
  • Paola Concolino
    • 1
  • Maria De Bonis
    • 1
  • Andrea Urbani
    • 1
    • 3
  • Giovanni Scambia
    • 2
    • 3
  • Anna Fagotti
    • 2
    • 3
  • Ettore Capoluongo
    • 4
  1. 1.Molecular and Genomic Diagnostics LaboratoryFondazione Policlinico Universitario A. Gemelli IRCCSRomeItaly
  2. 2.Gynecologic OncologyFondazione Policlinico Universitario A. Gemelli IRCCSRomeItaly
  3. 3.Università Cattolica del Sacro CuoreRomeItaly
  4. 4.Università Federico II-CEINGEBiotecnologie AvanzateNaplesItaly

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