Bionano Announces Publication Of Largest Prospective Prenatal Study Comparing OGM To Chromosomal Microarray Analysis And Karyotyping

Author: Happy Mohamed | December 26, 2023 09:13am

Key findings from prospective evaluation of 200 prenatal samples:
 

• Optical genome mapping (OGM) detected pathogenic structural variants (SVs) in 20.5% of samples (41/200); combination of chromosomal microarray analysis (CMA) and karyotyping (KT) detected pathogenic SVs in 19.5% of samples (39/200)
• Compared to CMA and KT combined in this prospective cohort, OGM had the following performance:
  • Sensitivity: 97.4%
  • Specificity: 100%
  • Positive Predictive Value (PPV): 100%
  • Negative Predictive Value (NPV): 99.4%
• For 8 copy number variants (CNVs) detected by CMA, OGM defined their location and orientation and revealed that they were 6 tandem duplications and 2 unbalanced cryptic translocations
• In 4% of samples (8/200), OGM identified D4Z4 repeat contractions on the permissive 4qA haplotype that may indicate facioscapulohumeral muscular dystrophy type 1 (FSHD1)

SAN DIEGO, Dec. 26, 2023 (GLOBE NEWSWIRE) -- Bionano Genomics, Inc. (NASDAQ:BNGO) today announced a publication covering the largest independent prospective prenatal study comparing optical genome mapping (OGM) to a combined workflow of chromosomal microarray analysis (CMA) and karyotyping (KT). The study highlighted OGM's high analytical concordance with the combined workflow of CMA and KT, and its ability to detect novel pathogenic structural variants (SVs) missed by those methods. The study also highlighted OGM's potential to provide additional information about SVs and copy number variants (CNVs) compared to CMA and KT.

The study, published by researchers from Nanjing Women and Children's Healthcare Hospital in China, reported that OGM demonstrated robust performance across multiple technical and analytical metrics when compared to CMA and KT. OGM also revealed the location and orientation of duplication segments, refined breakpoints of SVs and identified specific repeat contraction disorders that were not detected by other methods.

Researchers used 200 unique prospective prenatal samples with soft markers (including increased nuchal translucency, nasal bone hypoplasia and mild ventriculomegaly, and structural anomalies) for the study. Within this prospective cohort, OGM showed a 97.4% sensitivity, 100% specificity, 100% positive predictive value (PPV) and 99.4% negative predictive value (NPV) for detecting SVs reported with KT and CMA. OGM identified several additional SVs not detected by CMA and KT and defined location and orientation for eight CNVs, which may help researchers interpret the effect of CNVs more precisely. OGM also detected 8 D4Z4 repeat contractions on the permissive 4qA haplotype that may indicate facioscapulohumeral muscular dystrophy type 1 (FSHD1). The study authors concluded that OGM has the potential to serve as a first-tier cytogenetic method for prenatal analysis due to its ability to identify the majority of pathogenic SVs in a single assay.

"The use of OGM for the analysis of prenatal samples is an area where we believe our workflow can have tremendous global impact.  We believe this study marks a milestone in the Chinese prenatal research market as it includes the largest sample size to date for an independent prenatal study using OGM. Additionally, it demonstrates the workflow's strong performance and potential ability to provide answers from a single assay compared to the two to three assays required with the traditional methods commonly used today," commented Erik Holmlin, PhD, president and chief executive officer of Bionano.

The paper is available here.

Posted In: BNGO