Last reviewed: May 12, 2026 Last updated: May 12, 2026

Written by: Jay Hastings , CEO of PlexusDx

Jay Hastings is the CEO of PlexusDx, a precision health company focused on genetic testing, blood biomarker insights, and personalized wellness recommendations. He has more than 20 years of experience across healthcare innovation, genomics, laboratory operations, healthcare investing, and strategic finance. His work has included scaling healthcare startups, leading CLIA lab integrations, and helping expand consumer access to precision health tools.

Medically reviewed by: Jayden Lee, PharmD, EMBA

Jayden Lee, PharmD, EMBA, is the PlexusDx Medical Science Liaison with a PharmD and MBA specializing in pharmacogenomics and clinical product development, with a proven ability to bridge the gap between genomic research and practical patient outcomes. Dr. Lee has more than 10 years of professional experience in clinical pharmacy, academia, and research.

This article is part of the PlexusDx Education Hub — your resource for evidence-based guidance on injury & recovery. Browse all Injury & Recovery education

Some athletes tear a knee ligament from an awkward landing that a teammate walks away from unharmed. Training load, technique, and luck all play a role — but so does genetics. The proteins that build your ligaments, tendons, cartilage, and muscle are gene-encoded, and small inherited differences in those genes influence how much stress your knee can absorb before something gives. Knowing those factors can sharpen a prevention strategy.

Why some knees are more injury-prone

The knee is a mechanically demanding joint stabilized by ligaments, tendons, and cartilage — tissues built largely from collagen. Injury risk reflects how those tissues are constructed, how they respond to load, and how the surrounding muscles control movement. Genetics shapes each of these. Variation in collagen and joint-structure genes affects tissue stiffness and repair, while muscle-function genes influence power and control. None of this overrides training and technique, but it helps explain baseline differences in vulnerability.

Collagen genes: COL5A1 and COL1A1

Collagen is the structural backbone of ligaments and tendons, and two genes stand out in injury research. COL5A1 encodes a component of type V collagen; its rs12722 variant has been associated in multiple studies with anterior cruciate ligament (ACL) injury risk and with tendinopathy, likely by influencing tendon and ligament stiffness. COL1A1 encodes type I collagen, and a functional variant in its Sp1 binding site (rs1800012) has been linked in some populations to altered risk of cruciate ligament and soft-tissue injury. These variants shift the odds — they do not seal fate.

GDF5 and joint structure

GDF5 (growth differentiation factor 5) helps direct the development and maintenance of joints, cartilage, and connective tissue. A well-studied variant, rs143383, has been associated with osteoarthritis risk and with differences in joint structure that can influence how the knee tolerates load over time. Because GDF5 affects the joint's underlying architecture, it is relevant not only to acute injury but to long-term knee wear — a reminder that "injury risk" spans both the sudden tear and the slow degeneration.

Muscle and movement: ACTN3

Ligaments do not act alone; the muscles around the knee absorb force and control landing mechanics. ACTN3 encodes a protein in fast-twitch muscle fibers, and its R577X variant (rs1815739) influences muscle power and fiber composition. While ACTN3 is best known in athletic-performance research, muscle strength and neuromuscular control are central to knee stability. Genetic differences in muscle function are one more input into how well the joint is protected during high-demand movement.

What research shows about genetics and knee injury

Case-control and cohort studies have repeatedly associated collagen-gene variants with ACL rupture and tendon injury, though effect sizes are modest and findings vary across populations. The scientific consensus is that knee-injury risk is polygenic and multifactorial: many genes each contribute a little, and they interact with training volume, biomechanics, sex, and prior injury. No single test result predicts whether you will tear an ACL. What genetics offers is a probabilistic backdrop, not a verdict.

Pathway-level insight and a smarter prevention plan

Genetic testing does not prevent knee injuries, but it can inform how you approach prevention. The Precision Peptide Genetic Test analyzes 14 pathways, 49 peptides, 150+ genetic insights, including tissue-repair and connective-tissue pathways. Seeing where your biology sits can add context to a prevention conversation with a qualified provider or sports-medicine professional — who can weigh it alongside evidence-based staples like neuromuscular training, gradual load progression, and technique work. Genetics is a guide, not a guarantee, and the clinical decisions stay with your provider.

Frequently Asked Questions

Which genes are linked to knee injuries?

Collagen genes COL5A1 (rs12722) and COL1A1 (rs1800012) are associated with ACL and tendon injury risk, GDF5 (rs143383) with joint structure and osteoarthritis, and ACTN3 with muscle power and control. Each contributes modestly; knee-injury risk is polygenic and interacts strongly with training, biomechanics, and prior injury.

Can genetic testing predict if I will tear my ACL?

No. No genetic test predicts a specific injury. Variants like COL5A1 rs12722 shift population-level odds slightly but cannot forecast an individual outcome, which depends heavily on training load, technique, and chance. The Precision Peptide Genetic Test offers pathway-level context, not injury prediction or diagnosis.

How can I use genetic insight to prevent knee injuries?

Treat it as background, not a plan. Bring pathway-level insight into connective-tissue and muscle genes to a qualified provider or sports-medicine professional, who can pair it with proven prevention: neuromuscular training, gradual load progression, strength work, and sound technique. Genetics informs the conversation; the professional guides the program.

Does the Precision Peptide Genetic Test diagnose knee problems?

No. The test does not diagnose, treat, cure, or prevent any condition. It analyzes how your genes influence tissue-repair and connective-tissue pathways, giving you and your provider pathway-level context. Any diagnosis of a knee injury or joint condition requires clinical evaluation by a qualified healthcare professional.

Want to understand your connective-tissue pathways? Take the Precision Peptide Genetic Test to see how your DNA maps across 14 pathways, 49 peptides, 150+ genetic insights.

Disclaimer: The Precision Peptide Genetic Test analyzes how your genes influence peptide-related biological pathways. It does not recommend, prescribe, or determine which peptides you should use. Consult a qualified healthcare provider before beginning any peptide protocol.

This article is part of the PlexusDx Education Hub. Browse all Injury & Recovery education

Medical and Editorial Standards

Medical review process: This article was reviewed for medical accuracy, scientific clarity, evidence alignment, and appropriate discussion of genetics, medications, supplements, biomarkers, and health-related claims.

Sources and evidence: PlexusDx educational content is developed using peer-reviewed research, clinical literature, reputable medical references, and, where applicable, public health or regulatory guidance. References are included at the end of the article when scientific, medical, or health-related claims are discussed.

Commercial transparency: PlexusDx offers genetic testing, blood biomarker testing, personalized supplement recommendations, and related precision wellness services. Product mentions are intended to help readers understand available options and should not be interpreted as medical advice.

Important disclaimer: PlexusDx educational content is for informational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making decisions about medications, supplements, genetic testing, lab testing, or health-related care.