Evidence map›Paper›PMID 42125771›Full record

GuidelineBritish journal of clinical pharmacology2026

ACKR1/Duffy-null genotype testing for clozapine: A guideline developed by the UK Centre of Excellence in Regulatory Science and Innovation in Pharmacogenomics (CERSI-PGx).

Stephen Murtough, Oriella Stellakis, Daisy Mills, Blanca Bjourson, Vicky Chaplin, Dharmisha Chauhan, Bev Chipp, Marius Cotic, Jana de Villiers, Olubanké Dzahini and 20 more

Abstract readPractice Guideline
PubMed Full text at PMC Publisher
In one paragraph

Guideline in British journal of clinical pharmacology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed, 1 pooled it
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 1 synthesis or guideline pooled it.

  1. Guideline
  2. UGT1A1 and irinotecan: Ready for routine pharmacogenetic care.British journal of clinical pharmacology · 2026
    Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

30 authors.

Stephen MurtoughDivision of Psychiatry, University College London, London, UK.ORCID https://orcid.org/0000-0002-7440-7095
Oriella StellakisDivision of Psychiatry, University College London, London, UK.
Daisy MillsDivision of Psychiatry, University College London, London, UK.
Blanca BjoursonBelfast Health and Social Care Trust, Belfast, UK.
Vicky ChaplinGenomics Unit, National Health Service England, London, UK.
Dharmisha ChauhanNorth Thames Genomic Medicine Service Alliance, London, UK.
Bev ChippThe Side-By-Side Network, London, UK.
Marius CoticDivision of Psychiatry, University College London, London, UK.
Jana de VilliersThe Royal College of Psychiatrists, London, UK.
Olubanké DzahiniPharmacy Department, South London and Maudsley NHS Foundation Trust, London, UK.
Frances ElmslieSouth East Genomic Medicine Service Alliance, London, UK.
Katie EvansCardiff and Vale University Health Board, Cardiff, UK.ORCID https://orcid.org/0009-0006-7581-692X
Shreyans GandhiDepartment of Haematology, King's College Hospital NHS Foundation Trust, London, UK.
Dyfrig A HughesCentre for Health Economics and Medicines Evaluation, North Wales Medical School, Bangor University, Bangor, UK.ORCID https://orcid.org/0000-0001-8247-7459
Huajie JinKing's Health Economics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
Daniele PanconesiDivision of Psychiatry, University College London, London, UK.
Anna SkowronskaBirmingham Women's and Children's NHS Foundation Trust, Birmingham, UK.
Sanjay M SisodiyaResearch Department of Epilepsy, Queen Square Institute of Neurology, University College London, London, UK.
Ed SilvaSpecialist Community Forensic Team for People With Learning Disability and Autism, Hollins Park Hospital, Warrington, UK.
Vicky StintonNorth West Genomic Laboratory Hub, Manchester University NHS Foundation Trust, Manchester, UK.
Sara Stuart-SmithDepartment of Haematology, King's College Hospital NHS Foundation Trust, London, UK.
Sarah TarrantNHS Blood and Transplant, Bristol, UK.
David TaylorPharmacy Department, South London and Maudsley NHS Foundation Trust, London, UK.
Lauren VarneyDivision of Psychiatry, University College London, London, UK.
James T R WaltersCentre for Neuropsychiatric Genetics and Genomics, Division of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, UK.
Michelle WoodCardiff and Vale University Health Board, Cardiff, UK.
Jessica WoodleyBirmingham Women's and Children's NHS Foundation Trust, Birmingham, UK.
Cinzia Dello RussoDepartment of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK.ORCID https://orcid.org/0000-0002-2538-3832
Munir PirmohamedDepartment of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK.ORCID https://orcid.org/0000-0002-7534-7266
Elvira BramonDivision of Psychiatry, University College London, London, UK.ORCID https://orcid.org/0000-0003-1369-5983

Funding

Innovate UK
6 · The paper itself

Abstract

Clozapine is licenced for treatment-resistant schizophrenia and psychosis in Parkinson's disease. In the United Kingdom, there is a mandatory requirement for absolute neutrophil count (ANC) and white blood cell count (WBC) monitoring to safeguard against agranulocytosis. Some people have naturally low ANCs without increased infection risk, caused by a homozygous T > C variant in ACKR1, commonly called the Duffy-null genotype. This condition is known as ADAN (ACKR1/DARC-associated neutropenia) and synonyms include DANC (Duffy-null associated neutrophil count) and BEN (benign ethnic neutropenia). It is usual UK practice to lower WBC/ANC thresholds for people confirmed to have ADAN. However, ADAN often remains undetected, resulting in unnecessary discontinuation and exclusion from clozapine. This CERSI-PGx guideline provides a framework to offer ACKR1 genotype testing within the existing clinical pathway. We recommend three eligibility criteria, including pre-emptive testing for all people starting clozapine, testing for people registered in the Central Non-Rechallenge Database and reactive testing following a below-threshold blood result (defined as 'amber' or 'red'). We recommend that people with the Duffy-null genotype should be monitored using revised WBC/ANC thresholds for ADAN. Regardless of ACKR1 genotype, haematology input is required for people returning a WBC < 2.0 × 10

Indexed as

Antipsychotic AgentsClozapineDuffy Blood-Group SystemNeutropeniaPharmacogenomic TestingReceptors, Cell SurfaceGenotypeHumansLeukocyte CountPharmacogeneticsSchizophreniaSchizophrenia, Treatment-ResistantUnited KingdomACKR1 protein, humanAntipsychotic AgentsClozapineDuffy Blood-Group SystemReceptors, Cell SurfaceACKR1ACKR1/DARC‐associated neutropeniaclozapineDuffy‐null associated neutrophil countParkinson's diseasepharmacogenomicstreatment‐resistant schizophrenia

Identifiers

PMID42125771
PMCPMC13304278

What OpenQuestion holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.