{
 "id": "epe78tw9d4",
 "slug": "chromogenic-in-situ-hybridization",
 "title": "Chromogenic in situ hybridization",
 "updated": "2026-10-15",
 "topic_path": [
  {
   "id": "life",
   "label": "Life and health",
   "api_url": "https://www.edgepedia.org/api/v1/topics/life"
  },
  {
   "id": "life.health",
   "label": "Human health and medicine",
   "api_url": "https://www.edgepedia.org/api/v1/topics/life.health"
  },
  {
   "id": "life.health.clinical",
   "label": "Clinical assessment and procedures",
   "api_url": "https://www.edgepedia.org/api/v1/topics/life.health.clinical"
  },
  {
   "id": "life.health.clinical.clinical-diagnostics",
   "label": "Diagnosis and clinical assessment",
   "api_url": "https://www.edgepedia.org/api/v1/topics/life.health.clinical.clinical-diagnostics"
  },
  {
   "id": "life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics",
   "label": "Laboratory and in-vitro diagnostics",
   "api_url": "https://www.edgepedia.org/api/v1/topics/life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics"
  },
  {
   "id": "life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics.genetic-and-genomic-testing",
   "label": "Genetic and genomic testing",
   "api_url": "https://www.edgepedia.org/api/v1/topics/life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics.genetic-and-genomic-testing"
  }
 ],
 "geo": [
  {
   "id": "geo.nongeo.t1946.life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics.genetic-and-genomic-testing",
   "label": "Non-geographic · 1946 to 2000: Genetic and genomic testing",
   "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics.genetic-and-genomic-testing",
   "path": [
    {
     "id": "geo.nongeo",
     "label": "Non-geographic",
     "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo"
    },
    {
     "id": "geo.nongeo.t1946",
     "label": "Non-geographic · 1946 to 2000",
     "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946"
    },
    {
     "id": "geo.nongeo.t1946.life",
     "label": "Life and health",
     "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.life"
    },
    {
     "id": "geo.nongeo.t1946.life.health",
     "label": "Human health and medicine",
     "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.life.health"
    },
    {
     "id": "geo.nongeo.t1946.life.health.clinical",
     "label": "Clinical assessment and procedures",
     "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.life.health.clinical"
    },
    {
     "id": "geo.nongeo.t1946.life.health.clinical.clinical-diagnostics",
     "label": "Diagnosis and clinical assessment",
     "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.life.health.clinical.clinical-diagnostics"
    },
    {
     "id": "geo.nongeo.t1946.life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics",
     "label": "Laboratory and in-vitro diagnostics",
     "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics"
    },
    {
     "id": "geo.nongeo.t1946.life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics.genetic-and-genomic-testing",
     "label": "Genetic and genomic testing",
     "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics.genetic-and-genomic-testing"
    }
   ]
  }
 ],
 "excerpt": "Chromogenic in situ hybridization (CISH) is a pathology technique that detects specific DNA or RNA sequences in tissue sections, introduced in 2000 for HER2 testing in breast cancer.",
 "snippet": "Chromogenic in situ hybridization (CISH) is a pathology technique that detects specific DNA or RNA sequences in tissue sections, introduced in 2000 for HER2 testing in breast cancer.",
 "node": "life.health.clinical.clinical-diagnostics.laboratory-and-in-vitro-diagnostics.genetic-and-genomic-testing",
 "markdown": "# Chromogenic in situ hybridization\n\nChromogenic in situ hybridization (CISH) is a pathology technique that detects specific DNA or RNA sequences in tissue sections using labeled probes whose hybridization is visualized as enzyme-generated color precipitates under a light microscope. CISH was introduced for HER-2/neu amplification testing in archival breast cancer samples and is now used for gene copy number, viral transcripts, and microRNA biomarkers.\n\n| Key fact | Value |\n|---|---|\n| Output | Brown (DAB), red, green, or silver precipitate dots or clusters in nuclei, read on a bright-field microscope with a 40× objective (typically 400× total magnification) |\n| First validation vs FISH | Kappa 0.81 across 157 breast cancers (Tanner et al, 2000) <sup>[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC1885742/)</sup> |\n| Accuracy vs FDA-approved FISH | Sensitivity 95.7%, specificity 92.0%, concordance 93.8% in 192 paired cases <sup>[2](https://aacrjournals.org/clincancerres/article/10/14/4793/181787/Interlaboratory-Comparison-of-HER-2-Oncogene)</sup> |\n| Reagent cost per HER2 test | CAD$72.10 (CISH kit) vs CAD$132.50 (FISH kit) <sup>[3](https://www.nature.com/articles/6600943)</sup> |\n| Digital slide scanning | 29 sec/mm² for CISH vs 764 sec/mm² for FISH <sup>[4](https://pmc.ncbi.nlm.nih.gov/articles/PMC3870126/)</sup> |\n| Slide archiving | Signals do not decay; slides archive at room temperature and can be re-reviewed <sup>[3](https://www.nature.com/articles/6600943)</sup> |\n| Full protocol duration | 2–3 days for the basic FISH/CISH protocol <sup>[5](https://www.nature.com/articles/nprot.2007.534)</sup> |\n\n## How it works\n\nCISH relies on specific annealing (hybridization) of labeled probes to complementary nucleic acids within fixed cells, allowing detection, quantification, and spatial localization of the target sequence.<sup>[5](https://www.nature.com/articles/nprot.2007.534)</sup> Hapten-labeled probe fragments and their complementary targets are co-denatured and then allowed to anneal; an antibody-based detection system binds the hapten (small molecule that antibodies can bind, used to label probes), and an enzyme conjugate converts a chromogenic substrate into a colored precipitate at the hybridization site, which is read by light microscopy after nuclear counterstaining.<sup>[6](https://www.zytovision.com/downloads_products/manuals/en/t-1063-ce-ivd-en.pdf)</sup>\n\nThe common detection chemistry uses [digoxigenin](https://www.edgepedia.org/digoxigenin) (DIG)-labeled probes bound by anti-DIG antibody, then a horseradish peroxidase (HRP) polymer, then diaminobenzidine (DAB), which deposits brown precipitate; a multilayer anti-DIG–anti-fluorescein–HRP system was found to have superior sensitivity over direct immunodetection.<sup>[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC1885742/)</sup><sup> • </sup><sup>[6](https://www.zytovision.com/downloads_products/manuals/en/t-1063-ce-ivd-en.pdf)</sup> Dual-color versions pair haptens: DIG-labeled probes appear as dark green dots and dinitrophenyl (DNP)-labeled probes as bright red dots, developed with sequential alkaline phosphatase–red and HRP-green substrates.<sup>[7](https://www.zytovision.com/downloads_products/manuals/en/c-3044-ce-ivd-en.pdf)</sup>\n\nProbe design matters for specificity. The introducing study used a contig of two BAC clones with repetitive Alu and LINE sequences removed, because repeats cause unspecific hybridization.<sup>[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC1885742/)</sup> Commercial systems address repeats differently: one uses repeat-free oligonucleotides that need no blocking, while another developed Alu-blocking peptide nucleic acids to lower background in the HER2 DNA probe.<sup>[4](https://pmc.ncbi.nlm.nih.gov/articles/PMC3870126/)</sup> For short, highly similar RNA targets such as microRNAs, locked nucleic acid (LNA) probes labeled with DIG or FAM increase sensitivity and specificity.<sup>[8](https://experiments.springernature.com/articles/10.1007/978-1-4939-7172-5_22)</sup>\n\n## How it is done\n\nSpecimens are fixed in 10% neutrally buffered formalin for 24 h at room temperature (18–25 °C), with sample size ≤ 0.5 cm³, embedding below 65 °C, and 3–5 µm sections on positively charged slides.<sup>[6](https://www.zytovision.com/downloads_products/manuals/en/t-1063-ce-ivd-en.pdf)</sup> A representative manual workflow then runs: bake at 70 °C for 10 min; deparaffinize in xylene and 100% ethanol; block endogenous peroxidase with 3% H₂O₂; EDTA heat pretreatment at 98 °C for 15 min; pepsin digestion 5–15 min at 37 °C; ethanol dehydration; probe denaturation 5 min at 75 °C; hybridization 1 h at 37 °C for DNA targets or 55 °C for RNA targets; stringency wash 5 min in TBS wash buffer at 55 °C.<sup>[6](https://www.zytovision.com/downloads_products/manuals/en/t-1063-ce-ivd-en.pdf)</sup>\n\nDetection follows with primary anti-hapten antibody, enzyme polymer, and chromogen (for example anti-DIG 30 min, anti-mouse-HRP-polymer 30 min, DAB 20 min, all at 37 °C), then a light violet-blue nuclear counterstain.<sup>[6](https://www.zytovision.com/downloads_products/manuals/en/t-1063-ce-ivd-en.pdf)</sup> [Digestion](https://www.edgepedia.org/digestion) is the critical step: in a five-laboratory ring study, adjusting pepsin digestion yielded an interpretable result in 99% of cases (208 of 211).<sup>[9](https://link.springer.com/article/10.1186/bcr1776)</sup>\n\nReading the result: signals are counted per nucleus at 400× magnification and categorized (for example <5, 5, 6, or >6 HER2 spots), with at least 30 tumor cells scored, or 60 when 5–10 copies appear in over half the evaluated area.<sup>[9](https://link.springer.com/article/10.1186/bcr1776)</sup> Amplification typically appears as large peroxidase-positive intranuclear clusters <sup>[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC1885742/)</sup>, and dual-probe ISH scoring follows the current ASCO/CAP guidance, in which the HER2/CEP17 ratio (≥2.0 or <2.0) is combined with the average HER2 copy number (for example, ratio ≥2.0 with <4.0 signals per cell) and final HER2 status is determined with concomitant IHC review.<sup>[4](https://pmc.ncbi.nlm.nih.gov/articles/PMC3870126/)</sup>\n\n## Origin\n\nCISH was introduced by Tanner and colleagues in 2000, in a study that detected HER-2/neu gene copies in archival breast cancer samples with a conventional peroxidase reaction.<sup>[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC1885742/)</sup> It built on a lineage of in situ hybridization: hybridization of RNA-DNA hybrids at the cytological level was reported in 1969 <sup>[10](https://doi.org/10.1038/223582a0)</sup>, and quantitative high-sensitivity fluorescence hybridization, the basis of FISH, was reported by Pinkel, Straume, and Gray in 1986.<sup>[11](https://doi.org/10.1073/pnas.83.9.2934)</sup>\n\n## Variants\n\n**Dual-color CISH** converts Texas Red and FITC fluorescent FISH signals to chromogenic red (Fast Red) and blue signals via HRP- and AP-conjugated antibodies, allowing simultaneous HER2 and chromosome 17 assessment on one slide; it was reported for HER-2 testing in archival breast tumors by Laakso, Tanner, and Isola in 2006 in the Journal of Pathology.<sup>[12](https://doi.org/10.1002/path.2022)</sup><sup> • </sup><sup>[13](https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2559.2010.03503.x)</sup> A reliable method to generate CISH and FISH probes from pathology archives was reported by Lambros and colleagues in 2006 in Laboratory Investigation.<sup>[14](https://doi.org/10.1038/labinvest.3700390)</sup>\n\n**Automated bright-field platforms** include BDISH, which detects HER2 by silver deposition and CEN 17 by fast red on the Ventana BenchMark XT with DNP-labeled probes <sup>[15](https://diagnosticpathology.biomedcentral.com/counter/pdf/10.1186/1746-1596-3-41.pdf)</sup>, and DDISH, a fully automated dual-color dual-hapten method detecting both markers on a single slide.<sup>[16](https://www.sciencedirect.com/science/article/abs/pii/S0344033813000071)</sup> **SISH** (silver-enhanced in situ hybridization) is based on enzymatic metallography, producing discrete black silver deposits stable over time; the automated format reported in that 2010 study combines HER2 silver detection with a chromogenic red chromosome 17 probe and runs fully automated with results in up to 6 hours.<sup>[17](https://journals.lww.com/ajsp/fulltext/2010/08000/determination_of_the_her_2_neu_gene_amplification.13.aspx)</sup> **GOLDFISH** uses tyramide signal amplification with Nanogold and gold enhancement, producing large clusters for amplified HER2.<sup>[15](https://diagnosticpathology.biomedcentral.com/counter/pdf/10.1186/1746-1596-3-41.pdf)</sup> **IQ-FISH** reduces assay time from two days to four hours by using ethylene carbonate, rather than formamide, to destabilize the DNA helix.<sup>[4](https://pmc.ncbi.nlm.nih.gov/articles/PMC3870126/)</sup>\n\n**Chromogenic RNA ISH** extends the approach to single transcripts. RNAscope, reported by Wang and colleagues in 2011 in the Journal of Molecular Diagnostics, uses branched-DNA \"tree\" amplification with tandem Z-probes, so each punctum corresponds to one target mRNA molecule, and can be run with chromogenic detection on automated platforms.<sup>[18](https://doi.org/10.1016/j.jmoldx.2011.08.002)</sup><sup> • </sup><sup>[19](https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0207619)</sup> vsmCISH, reported by Jiang and colleagues in 2023 in RNA, achieves single-molecule RNA detection in clinical FFPE sections through DNA probe proximity ligation and rolling circle amplification: paired V probes mediate circle-probe circularization, Phi29 polymerase amplifies, and HRP-labeled probes with DAB render each product as a brown dot; its RCA step takes 2 hours instead of the conventional overnight reaction.<sup>[20](https://doi.org/10.1261/rna.079482.122)</sup>\n\n## Applications\n\n**HER2 testing in breast cancer** is the dominant clinical use. A five-laboratory ring study of 211 invasive breast carcinomas found 96% of FISH high-level amplified cases (HER2/CEP17 ratio >4.0) positive by CISH and 94% of FISH-negative cases (ratio <2.0) negative, with inter-laboratory concordance of 95% for normal copy number and 92% for ≥6 copies.<sup>[9](https://link.springer.com/article/10.1186/bcr1776)</sup> CISH also concords with immunohistochemistry: 92% for IHC 0/1+ and 91% for IHC 3+ cases, and among IHC 2+ (equivocal) cases it was 100% concordant with FISH high-level amplification.<sup>[9](https://link.springer.com/article/10.1186/bcr1776)</sup>\n\nOther settings include MYC-N copy-number analysis on tissue microarrays using DAB with hematoxylin counterstain <sup>[5](https://www.nature.com/articles/nprot.2007.534)</sup>, automated detection of human cytomegalovirus early-replication-phase RNA in FFPE renal graft biopsies <sup>[21](https://www.bjnephrology.org/en/article/validation-of-an-automated-chromogenic-in-situhybridization-protocol-for-detection-of-cytomegalovirus-in-formalin-fixedparaffin-embedded-renal-graft-biopsies/)</sup>, and one-day LNA-probe CISH for microRNA biomarker monitoring of drug safety and efficacy.<sup>[8](https://experiments.springernature.com/articles/10.1007/978-1-4939-7172-5_22)</sup> Image-analysis frameworks such as QuantISH, reported by Jamalzadeh and colleagues in 2022 in Laboratory Investigation, quantify cell type-specific target RNA expression from ISH slides.<sup>[22](https://doi.org/10.1038/s41374-022-00743-5)</sup>\n\n## Limitations and alternatives\n\n**Accuracy versus FISH.** Across published comparisons, average agreement between CISH and FISH for HER2 is 96% (SD 4%).<sup>[23](https://jcp.bmj.com/content/jclinpath/63/3/210.full.pdf)</sup> [Individual](https://www.edgepedia.org/individual) studies report kappa 0.81 in the introducing series <sup>[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC1885742/)</sup>, 93.8% concordance with sensitivity 95.7% and specificity 92.0% against PathVysion <sup>[2](https://aacrjournals.org/clincancerres/article/10/14/4793/181787/Interlaboratory-Comparison-of-HER-2-Oncogene)</sup>, 100% agreement for dual-color CISH <sup>[13](https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2559.2010.03503.x)</sup>, 98.9% for BDISH <sup>[15](https://diagnosticpathology.biomedcentral.com/counter/pdf/10.1186/1746-1596-3-41.pdf)</sup>, and 95.9% for DDISH.<sup>[16](https://www.sciencedirect.com/science/article/abs/pii/S0344033813000071)</sup> Discrepancies concentrate at low-level amplification: in the 4–10 HER2 copy range, FISH scores a HER2/CEP17 ratio while CISH counts copies directly, so polysomic cases can be called positive by CISH and negative by FISH.<sup>[9](https://link.springer.com/article/10.1186/bcr1776)</sup>\n\n**Enumeration limits.** In 81 cases (88% of CISH-amplified tumors), gene copies formed clusters that could not be enumerated; mean FISH copy number in those cases was 14.6 (SD 6.1), and CISH and FISH counts correlated at \\( r = 0.75 \\).<sup>[2](https://aacrjournals.org/clincancerres/article/10/14/4793/181787/Interlaboratory-Comparison-of-HER-2-Oncogene)</sup> Overlapping coalescing dots underestimate copy number in highly amplified nuclei <sup>[13](https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2559.2010.03503.x)</sup>, and overlapping nuclei in thick sections or particulate debris can bias counts.<sup>[3](https://www.nature.com/articles/6600943)</sup>\n\n**Technical failure modes.** Improper fixation, freezing, thawing, washing, drying, or sectioning produces artifacts or false results, and sections that dry out during or after hybridization develop cross-hybridization signals and noisy background.<sup>[6](https://www.zytovision.com/downloads_products/manuals/en/t-1063-ce-ivd-en.pdf)</sup> Excessive background can reflect endogenous HRP activity, controlled with a peroxidase block, or nonspecific protein interaction, controlled with serum- or casein-based blocking; over-counterstaining obscures specific signals.<sup>[24](https://biocare.net/wp-content/uploads/PDF%20Data%20Sheets/RI0207.pdf)</sup> [Chromosome](https://www.edgepedia.org/chromosome) 17 centromere co-testing would have been advantageous in roughly 7% of cases in one series <sup>[2](https://aacrjournals.org/clincancerres/article/10/14/4793/181787/Interlaboratory-Comparison-of-HER-2-Oncogene)</sup>, and single-color CISH requires retesting on a serial section when chromosome 17 polysomy is possible.<sup>[13](https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2559.2010.03503.x)</sup>\n\n**Practical advantages.** CISH costs less per test than FISH (CAD$72.10 vs CAD$132.50) <sup>[3](https://www.nature.com/articles/6600943)</sup>, reads on an ordinary bright-field microscope without oil-immersion lenses <sup>[15](https://diagnosticpathology.biomedcentral.com/counter/pdf/10.1186/1746-1596-3-41.pdf)</sup>, and its signals do not decay, so slides archive at room temperature for re-review and retrospective studies.<sup>[3](https://www.nature.com/articles/6600943)</sup><sup> • </sup><sup>[13](https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2559.2010.03503.x)</sup> For digital pathology, CISH scans far faster than FISH (29 vs 764 sec/mm²), and scanning failures are rarer because chromogenic slides lack autofocus, background, and autofluorescence problems; the same study concluded CISH is superior for high-throughput [HER2 testing](https://www.edgepedia.org/her2-testing) while IQ-FISH suits fast low-throughput work.<sup>[4](https://pmc.ncbi.nlm.nih.gov/articles/PMC3870126/)</sup> Interobserver agreement favors CISH over IHC (97.5% vs 84%).<sup>[25](https://pubmed.ncbi.nlm.nih.gov/16290155/)</sup>\n\n## References\n\n1. [Chromogenic in situ hybridization: a practical alternative for fluorescence in situ hybridization to detect HER-2/neu oncogene amplification in archival breast cancer samples (Am J Pathol 2000;157:1467-1472)](https://pmc.ncbi.nlm.nih.gov/articles/PMC1885742/)\n2. [Interlaboratory Comparison of HER-2 Oncogene Amplification as Detected by Chromogenic and Fluorescence in situ Hybridization (Tanner et al., Clin Cancer Res 2004)](https://aacrjournals.org/clincancerres/article/10/14/4793/181787/Interlaboratory-Comparison-of-HER-2-Oncogene)\n3. [Chromogenic in-situ hybridization: a viable alternative to fluorescence in-situ hybridization in the HER2 testing algorithm (Modern Pathology)](https://www.nature.com/articles/6600943)\n4. [Comparison of Fluorescence In Situ Hybridization and Chromogenic In Situ Hybridization for Low and High Throughput HER2 Genetic Testing (2013)](https://pmc.ncbi.nlm.nih.gov/articles/PMC3870126/)\n5. [Fluorescence and chromogenic in situ hybridization to detect genetic aberrations in formalin-fixed paraffin embedded material, including tissue microarrays (Summersgill, Clark & Shipley, Nat Protoc 2008)](https://www.nature.com/articles/nprot.2007.534)\n6. [ZytoFast PLUS CISH Implementation Kit HRP-DAB Instructions for Use (ZytoVision)](https://www.zytovision.com/downloads_products/manuals/en/t-1063-ce-ivd-en.pdf)\n7. [ZytoDot 2C CISH Implementation Kit Instructions for Use (ZytoVision)](https://www.zytovision.com/downloads_products/manuals/en/c-3044-ce-ivd-en.pdf)\n8. [Chromogenic In Situ Hybridization Methods for microRNA Biomarker Monitoring of Drug Safety and Efficacy (Methods in Molecular Biology)](https://experiments.springernature.com/articles/10.1007/978-1-4939-7172-5_22)\n9. [Chromogenic in situ hybridisation for the assessment of HER2 status in breast cancer: an international validation ring study (Breast Cancer Research 2009)](https://link.springer.com/article/10.1186/bcr1776)\n10. [H. A. JOHN, M. L. BIRNSTIEL, K. W. JONES (1969). RNA-DNA Hybrids at the Cytological Level. Nature.](https://doi.org/10.1038/223582a0)\n11. [D Pinkel, T Straume, J W Gray (1986). Cytogenetic analysis using quantitative, high-sensitivity, fluorescence hybridization.. Proceedings of the National Academy of Sciences.](https://doi.org/10.1073/pnas.83.9.2934)\n12. [M Laakso, M Tanner, J Isola (2006). Dual‐colour chromogenic in situ hybridization for testing of HER‐2 oncogene amplification in archival breast tumours. The Journal of Pathology.](https://doi.org/10.1002/path.2022)\n13. [Determination of HER2 amplification in primary breast cancer using dual-colour chromogenic in situ hybridization is comparable to fluorescence in situ hybridization: a European multicentre study involving 168 specimens (Histopathology 2010)](https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2559.2010.03503.x)\n14. [Maryou B K Lambros and colleagues (2006). Unlocking pathology archives for molecular genetic studies: a reliable method to generate probes for chromogenic and fluorescent in situ hybridization. Laboratory Investigation.](https://doi.org/10.1038/labinvest.3700390)\n15. [Development of automated brightfield double in situ hybridization (BDISH) application for HER2 gene and chromosome 17 centromere (CEN 17) for breast carcinomas (Diagnostic Pathology 2008)](https://diagnosticpathology.biomedcentral.com/counter/pdf/10.1186/1746-1596-3-41.pdf)\n16. [Comparison of dual-color dual-hapten brightfield in situ hybridization (DDISH) and fluorescence in situ hybridization in breast cancer HER2 assessment (Pathology - Research and Practice 2013)](https://www.sciencedirect.com/science/article/abs/pii/S0344033813000071)\n17. [Determination of the Her-2/neu Gene Amplification Status in Cytologic Breast Cancer Specimens Using Automated Silver-enhanced In-situ Hybridization (SISH) (Am J Surg Pathol 2010)](https://journals.lww.com/ajsp/fulltext/2010/08000/determination_of_the_her_2_neu_gene_amplification.13.aspx)\n18. [Fay Wang and colleagues (2011). RNAscope. Journal of Molecular Diagnostics.](https://doi.org/10.1016/j.jmoldx.2011.08.002)\n19. [A method for manual and automated multiplex RNAscope in situ hybridization and immunocytochemistry on cytospin samples (PLOS One)](https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0207619)\n20. [Meng Jiang and colleagues (2023). Single-molecule RNA in situ detection in clinical FFPE tissue sections by vsmCISH. RNA.](https://doi.org/10.1261/rna.079482.122)\n21. [Validation of an automated chromogenic in situ hybridization protocol for detection of cytomegalovirus in FFPE renal graft biopsies (Brazilian Journal of Nephrology)](https://www.bjnephrology.org/en/article/validation-of-an-automated-chromogenic-in-situhybridization-protocol-for-detection-of-cytomegalovirus-in-formalin-fixedparaffin-embedded-renal-graft-biopsies/)\n22. [Sanaz Jamalzadeh and colleagues (2022). QuantISH: RNA in situ hybridization image analysis framework for quantifying cell type-specific target RNA expression and variability. Laboratory Investigation.](https://doi.org/10.1038/s41374-022-00743-5)\n23. [Bright field in situ hybridisation for delineation of ERBB2 (HER2) status in breast carcinoma (Journal of Clinical Pathology review)](https://jcp.bmj.com/content/jclinpath/63/3/210.full.pdf)\n24. [RISH HRP Detection Kit data sheet (Biocare Medical)](https://biocare.net/wp-content/uploads/PDF%20Data%20Sheets/RI0207.pdf)\n25. [HER-2 gene amplification by CISH compared with FISH in breast cancer, a study of two hundred cases (Breast 2006)](https://pubmed.ncbi.nlm.nih.gov/16290155/)\n\n---\n*Topic: Encyclopedia › Life and health › Human health and medicine › Clinical assessment and procedures › Diagnosis and clinical assessment › Laboratory and in-vitro diagnostics › Genetic and genomic testing*\n\n*Initially written Sep 29, 2026 · Edited: Oct 15, 2026*\n\n*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*\n\nLicense: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license\n",
 "same_as": [],
 "url": "https://www.edgepedia.org/chromogenic-in-situ-hybridization",
 "markdown_url": "https://www.edgepedia.org/chromogenic-in-situ-hybridization.md",
 "license": {
  "name": "Edgepedia Community License 1.0",
  "url": "https://www.edgepedia.org/edgepedia/license",
  "summary": "Free with credit, commercial use included. AI training is open to everyone. For other uses, organizations over USD 100M in revenue or 100M monthly users license separately.",
  "spdx": "LicenseRef-Edgepedia-Community-1.0"
 },
 "credit": "\"Chromogenic in situ hybridization\", Edgepedia (EdgeChat), https://www.edgepedia.org/chromogenic-in-situ-hybridization. Edgepedia Community License 1.0.",
 "credit_md": "\"[Chromogenic in situ hybridization](https://www.edgepedia.org/chromogenic-in-situ-hybridization)\", Edgepedia (EdgeChat), [https://www.edgepedia.org/chromogenic-in-situ-hybridization](https://www.edgepedia.org/chromogenic-in-situ-hybridization). [Edgepedia Community License 1.0](https://www.edgepedia.org/edgepedia/license).",
 "credit_html": "\"<a href=\"https://www.edgepedia.org/chromogenic-in-situ-hybridization\">Chromogenic in situ hybridization</a>\", Edgepedia (EdgeChat), <a href=\"https://www.edgepedia.org/chromogenic-in-situ-hybridization\">https://www.edgepedia.org/chromogenic-in-situ-hybridization</a>. <a href=\"https://www.edgepedia.org/edgepedia/license\">Edgepedia Community License 1.0</a>.",
 "speakable": "Chromogenic in situ hybridization is a pathology technique that detects specific DNA or RNA sequences in tissue sections, introduced in 2000 for HER2 testing in breast cancer."
}