Evidence map›Paper›PMID 34256648›Full record

ArticleCephalalgia : an international journal of headache2021

The molecular clock gene cryptochrome 1 (

Carmen Fourier, Caroline Ran, Christina Sjöstrand, Elisabet Waldenlind, Anna Steinberg, Andrea Carmine Belin

Open access · hybridAbstract read
In one paragraph

Article in Cephalalgia : an international journal of headache, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
10citing papers in PubMed, 1 pooled it
2.2field-weighted citation impact, top 12% of its field
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

10 citing papers in PubMed, 1 synthesis or guideline pooled it, 26 citations in OpenAlex.

  1. Pooled it
  2. Hallmarks of primary headache: part 3 - cluster headache.The journal of headache and pain · 2025
    Review
  3. Reviewing the complex relationship between circadian rhythms and cluster headache.Cephalalgia : an international journal of headache · 2025
    Review
  4. Review
  5. Review
  6. Article
  7. Article
  8. Article
  9. Article
  10. Brain sciences · 2021
    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

6 authors at 2 institutions in 1 country.

Carmen FourierDepartment of Neuroscience, 27106Karolinska Institutet, Karolinska Institutet, Stockholm, Sweden.ORCID 0000-0001-6618-8948
Caroline RanDepartment of Neuroscience, 27106Karolinska Institutet, Karolinska Institutet, Stockholm, Sweden.ORCID 0000-0003-0239-9871
Christina SjöstrandDepartment of Clinical Neuroscience, 27106Karolinska Institutet, Karolinska Institutet, Stockholm, Sweden.
Elisabet WaldenlindDepartment of Clinical Neuroscience, 27106Karolinska Institutet, Karolinska Institutet, Stockholm, Sweden.
Anna SteinbergDepartment of Clinical Neuroscience, 27106Karolinska Institutet, Karolinska Institutet, Stockholm, Sweden.
Andrea Carmine BelinDepartment of Neuroscience, 27106Karolinska Institutet, Karolinska Institutet, Stockholm, Sweden.ORCID 0000-0001-6668-3172
Karolinska Institutet · SEKarolinska University Hospital · SE

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundCluster headache is a severe primary headache disorder commonly featuring a strikingly distinct circadian attack pattern. Therefore, the circadian system has been suggested to play a crucial role in the pathophysiology of cluster headache. Cryptochromes are key components of the molecular clock generating circadian rhythms and have previously been shown to be associated with several psychiatric disorders, including seasonal affective disorder, bipolar disorder, and depression.

methodsIn this case-control study, we investigated the role of cryptochrome (

resultsThe exonic

conclusionsWe discovered a disease-associated variant in the

Indexed as

Cluster HeadacheCryptochromesCase-Control StudiesCircadian RhythmHumansTranscription FactorsCRY1 protein, humanCryptochromesTranscription Factorscase-control studycircadian rhythmcluster headache geneticsgenetic association studymRNA expressionsingle nucleotide polymorphism

Identifiers

PMID34256648
PMCPMC8592106
OpenAlexW3177654936

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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.