Rainbow Genomics Presented at the 68th Annual Meeting of the American Society of Human Genetics

San Francisco, October 19, 2018

Title: “Mutation spectrum identified by germline testing of hereditary cancers from 500 healthy Chinese individuals using an accessible 30-gene panel following ACMG guidelines”

Introduction

Driven by rapid reduction of DNA sequencing cost and increased access to testing, significant progress has been made in the characterization of hereditary cancer variant carriers in the U.S. and European populations. In contrast, relatively few studies have been conducted in the Chinese population, especially regarding asymptomatic carriers of germline pathogenic variants.

With physician consultation and genetic counseling support, Hong Kong-based Rainbow Genomics has been providing hereditary cancer testing to both patients with cancer symptoms and healthy individuals, and the testing and reporting process follows current American College of Medical Genetics and Genomics (ACMG) guidelines. Here, we present the results of testing 559 healthy Chinese individuals by next-generation sequencing using a 30-gene panel, in collaboration with Color Genomics.

Methods

559 healthy Chinese individuals were tested using a 30-gene panel, which detects pathogenic variants associated with increased risk for 8 hereditary cancers - Breast, ovarian, uterine/endometrial, colorectal, melanoma, pancreatic, prostate, and stomach cancer (APC, ATM, BAP1, BARD1, BMPR1A, BRCA1, BRCA2, BRIP1, CDH1, CDK4, CDKN2A (p14ARF and p16INK4a), CHEK2, EPCAM, GREM1, MITF, MLH1, MSH2, MSH6, MUTYH, NBN, PALB2, PMS2, POLD1, POLE, PTEN, RAD51C, RAD51D, SMAD4, STK11, and TP53). Blood samples were collected in Hong Kong and shipped to the U.S.

The testing was performed at Color’s U.S. laboratory under CLIA and CAP compliance using next-generation sequencing methods. English and Chinese clinical reports, localized pre-test consultation, and post-test genetic counseling in Mandarin or Cantonese were provided.

Conclusions

  • The test results indicate that pathogenic or likely pathogenic variants associated with 8 hereditary cancers were detected in approximately 6% of 559 healthy Chinese individuals

  • For healthy women (n=486), accounting for breast, ovarian, uterine and colorectal cancers, the aggregated pathogenic variant carrier rate for one, two, three or all four cancers is 6%

  • The mutation spectra of both breast and ovarian cancers indicate that more than just a few “well-established” genes (such as BRCA1/2) confer elevated cancer risk, reconfirming the utility of multi-gene panels for screening or even diagnostic objectives previously reported