Company: BLLN
Filing Date: 2025-10-07
Form Type: S-1
Source: 0001193125-25-233697
Chunk: 13

Company: BillionToOne, Inc.
Filing Date: 2025-10-07
Form: S-1
Chunk 13
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-related diagnostics

Methylation: A biochemical process where a methyl group (a carbon atom bonded to three hydrogen atoms) is added to a molecule, such as DNA. This process can
change gene expression levels (increase expression of or silence genes). Hypermethylation of certain genes (e.g., those involved in regulation of cell division), is a hallmark for cancer

Mis-priming errors: One of the errors caused by PCR amplification during library preparation for NGS. Mis-priming errors occur when primers mistakenly stick to
the incorrect region of test DNA, leading to the amplification of unintended or incorrect results

MolDX: Molecular Diagnostic Services program –
establishes coverage and reimbursement for Medicare beneficiaries

MRD: Minimal residual disease—When a minimal amount of circulating tumor DNA shed
from cancer cells remain after surgery or treatment

NGS:Next-generation sequencing refers to various high-throughput DNA sequencing technologies that have
enabled rapid and comprehensive analysis of genetic material

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NIPT: Non-invasive prenatal testing—Testing that uses cell-free
DNA from maternal blood to assess fetal genetic risks

Non-specific binding bias: One of the biases caused by PCR amplification during library preparation for
NGS. Non-specific binding bias occurs when DNA, proteins, or assay reagents bind to unintended targets, leading to reduced specificity, false-positive results, background noise, and ambiguity in test interpretation

PCR:Polymerase Chain Reaction—A laboratory technique that amplifies, or creates multiple copies of, a specific DNA sequence. PCR, initially developed in
1980s, is one of the most commonly used methods in molecular diagnostics. While PCR is still used as an initial step in many diagnostics for amplifying DNA, other methods (e.g., first Sanger sequencing and then NGS), have been used as a more precise
read-out in diagnostics over time

Primer binding bias: One of the biases caused by PCR amplification during library preparation for NGS. Primer binding bias
occurs when different PCR primers in a multiplex reaction are exponentially amplified at different rates, leading to dramatic differences in end-point PCR abundances of different sequences

QCT: Quantitative Counting Templates—BillionToOne’s patented synthetic DNA fragments that are the foundation of the smNGS platform. See
“Business—Our Technology—The components of our platform—Quantitative Counting Templates (QCTs)”

Sample accessioning:The
process in a laboratory where incoming specimens are received, logged, labeled, and