Learn Genetics

Learn genetics — reading pathways from foundations to advanced

A free, structured reading library through the molecular, clinical, population, quantitative, cancer, and therapeutic genetics topics taught at MSc / FRCPath level. Seven pathways take a reader from secondary-school biology through to topics covered in postgraduate genetics curricula; each pathway pairs ordered reading with Evagene's calculator and pedigree-drawing demonstrations so the theory stays attached to a worked example.

Free to read in the browser. No registration, no enrolment, no paywall. This is a supplement to formal training, not a substitute for it — professional examinations such as the FRCPath require supervised case exposure, breadth, and assessment that no web library replicates. For academic, research, and teaching use; not clinical decision support, not a medical device.

Last reviewed: 7 May 2026 · Next scheduled review: November 2026 · about this content

How this page works

Each pathway is an ordered sequence of pages with a defined audience and a stated prerequisite. Reading times are estimates for careful reading (15–30 min per page); a full pathway runs 5–12 pages or 2–6 hours. After the pathway sections, a topic browser lists every page organised by major topic, so anyone who prefers to dip in can browse freely. An Apply What You've Learned section routes to Evagene's risk-model calculators and pedigree-drawing tool, most of which are demonstrated through the alpha programme. Inspired by learn.microsoft.com's structured-pathway approach, but for genetics.

Every educational page cites primary peer-reviewed sources (PubMed, NCBI, OMIM, GeneReviews, Nature, NEJM, Annual Reviews, ENCODE, gnomAD). Evagene is a research-, education-, and family-history-focused platform; the pages are educational summaries, not clinical advice.

About this content

Authorship and review. Pages are drafted by the Evagene editorial team against primary peer-reviewed sources, checked for current versions of evolving standards (NSGC pedigree nomenclature, ACMG/AMP variant interpretation, ACMG SF list, ISCN, HPO, GA4GH), and dated with a "Last reviewed" timestamp. We do not currently operate a formal external editorial board; for the most rigorous use, particularly in clinical genetics, counselling, variant interpretation, and risk-model contexts, read alongside formal teaching and supervision and cite primary sources directly.

Conflict of interest. Evagene publishes both this learning library and the calculator / pedigree-drawing tool that the Apply sections link to. Where the educational content discusses Evagene's tools, the framing is informational, not promotional; where it discusses competitor tools (for example BOADICEA at canrisk.org or the IBIS Tyrer-Cuzick binary), it routes readers to those canonical sources directly. Comparative claims about products are dated and sourced.

Currency. Genetics moves quickly. ACMG SF v3.3 (2025), CanRisk v3 with BOADICEA breast cancer v7, AlphaMissense (2023), and the Casgevy / exa-cel approvals are recent examples of standards or evidence that pages need to track. Pages carry a "Last reviewed" date; the version of an evolving standard cited on a page is current as of that date but may have superseded since. Always check the publishing organisation's site (acmg.net, canrisk.org, omim.org) for the latest version.

Errors and corrections. If you spot an error or out-of-date reference, contact us via the alpha waiting list page; corrections are noted with the next "Last reviewed" date.

Educational versus clinical use. The reading pages and the calculator demonstrations are designed for academic, research, and teaching use, and for personal family-history documentation. They are not clinical decision support, not diagnostic, and not a medical device. The alpha app has separate Terms covering data handling that differ from the Privacy Policy applied to evagene.com itself; the alpha is not for real patient data. Read the Terms before signing up.

Pick your pathway

Pathway 1

Foundations

Genetics from scratch. From DNA structure to inheritance patterns. ~6–7 hours, 11 pages.

 Pathway 2

Molecular biology deep dive

DNA, transcription, translation, regulation, epigenetics, networks. ~10–12 hours, 13 pages.

 Pathway 3

Clinical genetics

Pedigree-taking, ACMG/AMP variant interpretation, counselling, ELSI. ~8–10 hours, 12 pages.

 Pathway 4

Cancer genetics

Oncogenes / tumour suppressors, hereditary syndromes, somatic genomics. ~7–9 hours, 9 pages.

 Pathway 5

Population & quantitative

Hardy-Weinberg, polygenic risk scores, heritability, GxE, ELSI. ~6–8 hours, 8 pages.

 Pathway 6

Therapeutics & gene therapy

IEM, pharmacogenetics, haemoglobin disorders, CRISPR, Casgevy. ~5–6 hours, 6 pages.

 Pathway 7

Refresher: recent advances

For practitioners. AlphaMissense, ACMG SF v3.3, NSGC 2022, PRS, Casgevy, polygenic embryo selection. ~4–5 hours, 7 pages.

 Alternative

Browse by topic

All 46 educational pages organised under the 12 major topics. Self-directed reading.

 Practice

Apply what you've learned

Twenty risk-model calculators plus the in-browser pedigree drawing tool. Theory meets practice.

Pathway 1

Foundations — genetics from scratch

Audience: students with secondary-school biology, beginning undergraduates, curious adults, anyone returning to genetics after a long gap. Prerequisite: familiarity with the concepts of "DNA", "gene", and "chromosome" at school-leaving level. Time: ~6–7 hours of careful reading. Outcome: ability to read a pedigree, identify common inheritance patterns, explain how mutations cause disease, and follow most undergraduate genetics teaching.

  1. 1.
    Pedigree chart · 10 min

    A visual entry to genetics. The diagrammatic vocabulary used by every clinician and most textbooks.

  2. 2.
    Inheritance patterns · 15 min

    Autosomal dominant / recessive, X-linked, Y-linked, mitochondrial, imprinting. The classical Mendelian set.

  3. 3.
    DNA and chromatin organisation · 20 min

    Watson-Crick base pairing, the double helix, packaging into chromatin and chromosomes.

  4. 4.
    Mendelian genetics and gene discovery · 20 min

    Mendel 1866 to GWAS 2007. How specific genes are found.

  5. 5.
    Chromosomes and cell division · 20 min

    Mitosis, meiosis, recombination, the cell cycle.

  6. 6.
    Chromosomal abnormalities · 20 min

    Aneuploidy (Down, Edwards, Patau, Turner, Klinefelter), translocations, microdeletion syndromes.

  7. 7.
    Mutation biology and consequences · 20 min

    What a mutation is, what causes one, what the consequences are.

  8. 8.
    Types of mutation · 20 min

    Point mutations, indels, repeat expansions (Huntington, fragile X), structural variants.

  9. 9.
    Gene expression mechanisms · 20 min

    DNA → RNA → protein, in plain language. Read for the headlines, not the detail.

  10. 10.
    Pedigree analysis and variable expression · 25 min

    Penetrance, expressivity, mosaicism, Bayesian risk calculation. Where pedigrees become quantitative.

  11. 11.
    Allele frequency dynamics · 25 min

    Hardy-Weinberg, selection, drift. Why sickle cell is common in malaria-endemic regions.

Apply

Try the Mendelian inheritance calculator, the autosomal dominant and recessive calculators, and draw your first pedigree with the pedigree drawing tool.

Pathway 2

Molecular biology deep dive

Audience: undergraduate molecular biology / biochemistry students, MSc candidates, anyone who wants to understand how genes are read, regulated, and repaired at the molecular level. Prerequisite: Foundations Pathway or equivalent undergraduate biology. Time: ~10–12 hours. Outcome: ability to explain transcription, splicing, translation, chromatin regulation, and DNA repair pathways at a level appropriate for first-year postgraduate work.

  1. 1.
    Molecular architecture of genes · 20 min

    Survey of the molecular topics. Read first to map the territory.

  2. 2.
    DNA and chromatin organisation · 20 min

    Watson-Crick / Hoogsteen, base-pairing energetics, supercoiling, nucleosomes, TADs.

  3. 3.
    DNA replication and repair · 25 min

    Replisome, polymerases, MMR, NER, BER, HR vs NHEJ. The wiring behind Lynch syndrome and BRCA-related cancer.

  4. 4.
    Genome structure and variation · 25 min

    Repetitive DNA, transposons, CNV, SV detection, gnomAD-SV, long-read sequencing.

  5. 5.
    Gene expression mechanisms · 20 min

    Pillar overview — central dogma, the four stages.

  6. 6.
    Transcriptional machinery · 25 min

    Pol I/II/III, the CTD cycle, promoters, Mediator, enhancer-promoter contact.

  7. 7.
    RNA processing and stability · 25 min

    Spliceosome, alternative splicing, polyadenylation, NMD.

  8. 8.
    Translation and post-translational control · 25 min

    Ribosome structure, eIFs, mTOR, ribosome profiling, chaperones, PTMs.

  9. 9.
    Regulation of gene activity · 20 min

    Pillar overview of the three regulatory layers.

  10. 10.
    Cis and trans regulatory elements · 25 min

    Enhancers, silencers, insulators, super-enhancers; ChIP-seq / ATAC-seq; eQTLs.

  11. 11.
    Epigenetics and chromatin dynamics · 25 min

    DNA methylation, histone marks, ChromHMM, Polycomb, X-inactivation, loop extrusion.

  12. 12.
    Gene regulatory networks · 25 min

    Network motifs, miRNAs, lncRNAs, Perturb-seq.

  13. 13.
    Functional consequences of mutation · 20 min

    LoF, GoF, dominant negative, splice and regulatory mutations. Closing the molecular-to-disease loop.

Pathway 3

Clinical genetics — for trainees and counsellors

Audience: genetic counselling MSc students, clinical genetics specialty trainees, FRCPath molecular pathology candidates, GPs and oncologists adding genetics to their practice. Prerequisite: Foundations Pathway or equivalent undergraduate biology + a clinical / counselling role context. Time: ~8–10 hours. Outcome: a working understanding of how a clinical genetics consultation captures family history, classifies variants under the published ACMG/AMP framework, and routes to counselling and disclosure. Pages describe the published professional literature; they are not clinical advice.

  1. 1.
    Clinical pedigree drawing · 15 min

    NSGC 2022 conventions, three-generation capture, consanguinity, pregnancy outcomes.

  2. 2.
    NSGC pedigree notation · 15 min

    Symbol set in detail: 1995 / 2008 / 2022.

  3. 3.
    Clinical genetic skills · 20 min

    The structured family-history interview, dysmorphology, ethnically informed history.

  4. 4.
    Inheritance patterns · 20 min

    Recap; you will use these recurrently in clinic.

  5. 5.
    Pedigree analysis and variable expression · 25 min

    Bayesian carrier-probability calculation; penetrance, expressivity, mosaicism.

  6. 6.
    Mutation detection and interpretation · 25 min

    NGS pipelines, ACMG/AMP 5-tier classification, gnomAD, ClinVar, AlphaMissense.

  7. 7.
    Diagnostics and counselling · 25 min

    Test taxonomy, secondary findings (ACMG SF v3.3), Reciprocal-Engagement Model, cascade testing, duty to warn.

  8. 8.
    Cancer genetics and somatic variation · 20 min

    Pillar overview — oncogenes / tumour suppressors / inherited / somatic.

  9. 9.
    Inherited cancer predisposition · 25 min

    HBOC, Lynch, FAP, Li-Fraumeni, the major hereditary syndromes; published surveillance literature.

  10. 10.
    Clinical practice, ethics, and communication · 20 min

    Pillar overview of the consultation, counselling, and ELSI dimensions.

  11. 11.
    Ethics, legal, and social issues · 25 min

    NHGRI ELSI, GINA, GDPR, duty to warn, equity in genomics.

  12. 12.
    Clinical pedigree drawing guidelines · 15 min

    Bennett 1995 / 2008 / 2022, ISCN, HGNC, HPO — the standards reference.

Apply

Use the pedigree drawing tool on a real family-history scenario. Try the BRCAPRO, MMRpro, and Lynch syndrome risk calculators on a worked pedigree. Review hereditary cancer risk assessment for the integrated workflow.

Pathway 4

Cancer genetics

Audience: oncology, cancer-genetics counsellors, molecular-pathology trainees, researchers in tumour biology. Prerequisite: Foundations or undergraduate biology, plus the Mutation Biology subset of the Molecular Biology pathway. Time: ~7–9 hours. Outcome: ability to read a tumour sequencing report, distinguish driver from passenger mutations, recognise the major hereditary cancer syndromes, and follow the published literature on mutational signatures and biomarker-targeted therapy.

  1. 1.
    Cancer genetics and somatic variation · 20 min

    Pillar — Knudson, Hanahan & Weinberg hallmarks, the three sub-themes.

  2. 2.
    Mutation biology and consequences · 20 min

    Pillar — types and consequences of mutation.

  3. 3.
    Types of mutation · 20 min

    SNVs, indels, repeat expansions, mutational signatures, paternal age effect.

  4. 4.
    Functional consequences of mutation · 20 min

    LoF / GoF / dominant negative; splice and regulatory mutations; TERT promoter.

  5. 5.
    Oncogenes and tumour suppressors · 25 min

    RAS / MYC / BCR-ABL / HER2 / EGFR / BRAF; RB1, TP53, APC, BRCA1/2; gatekeeper / caretaker / landscaper.

  6. 6.
    Inherited cancer predisposition · 25 min

    HBOC, Lynch, FAP, MAP, Li-Fraumeni, Cowden, Peutz-Jeghers, HDGC, VHL, MEN1/2, NF, TSC, retinoblastoma.

  7. 7.
    Somatic genomics · 25 min

    Clonal evolution, ctDNA, CHIP, mutational signatures, HRD, MSI, TMB, biomarker-targeted therapy.

  8. 8.
    Mutation detection and interpretation · 25 min

    NGS pipeline, ACMG/AMP, in-silico predictors, ClinVar, gnomAD.

  9. 9.
    Hereditary cancer risk assessment · 30 min

    The integrated workflow: family history → published risk-model algorithms → published referral thresholds.

Apply

Run worked examples through BRCAPRO, MMRpro, PancPRO, and the Lynch syndrome risk calculator. Compare BOADICEA vs BRCAPRO. Explore the germline mosaicism calculator for de-novo-mutation counselling.

Pathway 5

Population & quantitative genetics

Audience: population-genetics researchers, statistical-genetics MSc students, epidemiologists, anyone working with PRS or GWAS. Prerequisite: Foundations Pathway plus comfort with basic statistics. Time: ~6–8 hours. Outcome: ability to read GWAS / PRS literature, evaluate heritability estimates, recognise the limits of polygenic prediction, and engage with the equity / portability debates.

  1. 1.
    Population and evolutionary genetics · 20 min

    Pillar — Hardy 1908, Wright 1931, Kimura 1968, the conceptual map.

  2. 2.
    Allele frequency dynamics · 25 min

    Hardy-Weinberg, selection, drift, the coalescent.

  3. 3.
    Demography and population structure · 25 min

    F-statistics, PCA, ADMIXTURE, founder effects, demographic inference, ancient DNA.

  4. 4.
    Quantitative and complex traits · 20 min

    Pillar — Fisher's polygenic synthesis, Falconer's threshold model.

  5. 5.
    Polygenic models · 25 min

    Fisher's infinitesimal model, polygenic risk scores, PGS Catalog, portability.

  6. 6.
    Heritability and liability · 25 min

    Twin / SNP heritability, GREML, LDSC, missing heritability, threshold model, Carter effect.

  7. 7.
    Gene-environment interaction · 25 min

    GxE designs, Mendelian randomisation, epigenetic mediation.

  8. 8.
    Population genetics applications · 25 min

    Carrier-screening epidemiology, Wilson-Jungner criteria, ELSI of population screening.

Apply

Explore complex-disease pedigree software for the liability-threshold engine in practice. Use the consanguinity calculator for Wright's coefficient on a worked pedigree.

Pathway 6

Therapeutics & gene therapy

Audience: pharmacy / clinical pharmacology trainees, paediatricians and metabolic specialists, anyone interested in CRISPR and gene therapy. Prerequisite: Foundations or undergraduate biology. Time: ~5–6 hours. Outcome: a working understanding of inborn errors of metabolism, the published pharmacogenetic evidence base (CPIC), and the current generation of approved gene-therapy products (Casgevy, Luxturna, Zolgensma, Spinraza). Pages describe the published research literature; nothing here is a treatment recommendation.

  1. 1.
    Metabolic genetics and therapeutics · 20 min

    Pillar — Garrod 1902 to CRISPR 2024.

  2. 2.
    Inborn errors of metabolism · 25 min

    Pathway-block reasoning, NBS, IEM categories.

  3. 3.
    Pharmacogenetics and precision therapy · 25 min

    CYP polymorphisms, HLA-B*57:01 and abacavir, CPIC, Luxturna, Zolgensma, Spinraza, CRISPR-Cas9, base / prime editing, exa-cel.

  4. 4.
    Haemoglobin and development genetics · 20 min

    Pillar — Pauling 1949, Ingram 1957, Nüsslein-Volhard 1980.

  5. 5.
    Haemoglobin biology and disorders · 25 min

    α / β / γ / δ chains, the haemoglobin switch, sickle cell, thalassaemia genetics, CRISPR exa-cel.

  6. 6.
    Genes in development · 25 min

    WNT, SHH, Notch, BMP/TGF-β, FGF, Hippo signalling; congenital malformation genetics.

Pathway 7

Refresher — recent advances

Audience: qualified clinicians, counsellors, researchers, and educators who learned the foundations several years ago and want a tightly focused update on what has changed since 2020. Prerequisite: existing working knowledge of clinical genetics. Time: ~4–5 hours. Outcome: caught up on AlphaMissense, ACMG SF v3.3 (Miller 2025; adds ABCD1, CYP27A1, PLN), NSGC 2022, CanRisk v3 with BOADICEA breast cancer v7, mutational signatures (PCAWG), Casgevy, polygenic embryo selection, and the equity-in-genomics literature.

  1. 1.
    Mutation detection and interpretation · 25 min

    AlphaMissense (Cheng 2023), AlphaFold-derived predictors, gnomAD v4, ACMG/AMP refinements (Tavtigian 2018; Brnich 2019).

  2. 2.
    Diagnostics and counselling · 25 min

    ACMG SF v3.3 (Miller 2025) adds ABCD1, CYP27A1, PLN; the list keeps growing.

  3. 3.
    Pedigree analysis and variable expression · 20 min

    NSGC 2022 (Bennett 2022) on sex versus gender; the symbol-set update most likely to land in your clinic.

  4. 4.
    Somatic genomics · 25 min

    Mutational signatures (Alexandrov 2020 PCAWG), HRD, MSI-H + checkpoint inhibitors (Le 2015), TRACERx clonal evolution.

  5. 5.
    Polygenic models · 25 min

    PRS construction (LDpred, PRS-CS), Khera 2018 CAD score, Martin 2019 portability, the PGS Catalog.

  6. 6.
    Pharmacogenetics and precision therapy · 25 min

    CRISPR-Cas9 editing in clinical use, base / prime editing, the Casgevy / exa-cel approval (Frangoul 2021; FDA / MHRA 2023).

  7. 7.
    Ethics, legal, and social issues · 25 min

    Polygenic embryo selection (Karavani 2019; Turley 2021), the Genomics England Newborn Genomes Programme, ABC v St George's [2020], equity in genomics (Sirugo 2019).

Alternative

Browse by topic

All 46 educational pages organised under the 12 major topics. For self-directed reading or for finding a specific page outside the pathway structure.

Molecular architecture of genes

Gene expression mechanisms

Regulation of gene activity

Mutation biology and consequences

Chromosomes and cell division

Mendelian genetics and gene discovery

Quantitative and complex traits

Population and evolutionary genetics

Haemoglobin and development

Cancer genetics and somatic variation

Metabolic genetics and therapeutics

Clinical practice, ethics, and communication

Practice

Apply what you've learned

The pages explain the published methods; the pages below let you run them. The reading material is free without registration. The interactive calculators and pedigree-drawing tool are demonstrated through the Evagene alpha programme — usable today, but require joining the alpha waiting list for hands-on practice. Outputs are illustrative and intended for research, teaching, and family-history documentation.

Before you use the tools — honest caveats

  • Risk-model limitations. Even widely-validated models (BRCAPRO, MMRpro, PancPRO, Tyrer-Cuzick, BOADICEA) carry calibration limits in under-represented ancestries, depend on the completeness of the family history entered, and use thresholds validated in specific populations. Recent BOADICEA updates (breast cancer v7, ovarian v3) introduce UK ethnicity-specific parameters that older CanRisk file formats do not carry. Treat outputs as illustrative; for clinical risk computation, route to the canonical clinical-grade source (canrisk.org for BOADICEA; the official IBIS binary for Tyrer-Cuzick).
  • Family-history data implicates relatives. A pedigree records information about people who have not personally consented to its capture. The AI-assisted draft summary features and the Pedigree Builder GPT both ingest family-structure data. Use anonymised or fictional families for teaching and research demonstrations; the alpha is not for real patient data.
  • Alpha access. Most calculator and tool pages link into the Evagene alpha. The alpha is free during the programme but requires the waiting list. The alpha is for research, teaching, and family-history documentation; it is not certified for clinical use, and the alpha Terms differ from the marketing-site Privacy Policy — read the Terms before signing up.

Draw & document

Mendelian inheritance

Cancer family-history risk

Specialised tools

Worked condition examples

Inheritance-model deep dives

Frequently asked questions

Who is this learning library for?

Students with secondary-school or undergraduate biology, trainees in clinical and laboratory genetics, MSc and FRCPath candidates, educators preparing teaching material, genetic counsellors and clinical geneticists wanting a structured refresher, and curious practitioners from adjacent fields. The pathways are layered so the same library serves a beginner working from foundations and a practitioner skimming recent advances.

How much background knowledge do I need to start?

The Foundations pathway assumes secondary-school biology only. The Molecular Biology, Cancer Genetics, and Population pathways assume undergraduate-level biology. The Clinical and Refresher pathways assume working knowledge of pedigree drawing and inheritance patterns; if you don't have that, start with Foundations.

How long does each pathway take?

Each page is 1,000 to 2,000 words and takes 15 to 30 minutes to read carefully. A pathway is typically 5 to 12 pages, so 2 to 6 hours. Many readers spread a pathway over several sessions; nothing is timed.

Are the pages free to use?

Yes. Free in the browser, no registration, no paywall. For academic, research, and teaching use; not clinical decision support, not a medical device.

Can I cite Evagene's pages in my own teaching?

Yes. Each page cites primary peer-reviewed sources (PubMed, NCBI, OMIM, GeneReviews, Nature, NEJM, Annual Reviews, ENCODE, gnomAD). The most rigorous practice is to cite the primary sources directly; Evagene pages can be referenced as a teaching summary.

How does this differ from a textbook?

Pages are deliberately shorter and more focused than textbook chapters. Each targets one topic and links to related pages. The Apply What You've Learned sections route to working risk-model implementations and the pedigree drawing tool. Use alongside a textbook (Strachan & Read; Korf & Irons; Nussbaum / McInnes / Willard), not as a replacement.

Ready to apply what you've learned?

Draw your first pedigree, run a worked example through twenty published risk-model algorithm implementations, and explore the 1,900-entry help catalogue. Free during alpha for clinicians, researchers, educators, and students.

Join the Alpha Waiting List