28 citations
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March 2014 in “Biological reviews/Biological reviews of the Cambridge Philosophical Society” The document concludes that hair curvature can be explained by the growth patterns caused by the shape and separation of cells in the hair follicle and is affected by specific molecular pathways.
December 2023 in “Data in Brief” Curly hair's strength and flexibility vary with moisture and temperature.
4 citations
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June 2021 in “Scientific Reports” Hair fiber shape and curvature are not significantly linked when ancestry is considered.
July 2024 in “Journal Archives of Health” Woolly hair is a rare genetic condition with no effective treatments.
1 citations
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July 2024 in “International Journal of Cosmetic Science” Hair curvature is the main factor affecting curly hair manageability and product preferences.
February 2019 in “PubMed” The research found that twisting hair fibers can show changes in stiffness and damage, and help tell apart different hair treatments.
Yak hair stretches mainly due to macromolecules slipping past each other.
12 citations
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January 2013 in “Indian dermatology online journal” The document reports a unique case of woolly hair with a combination of conditions not previously seen together.
7 citations
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January 2012 in “International Journal of Trichology” A man with Woolly Hair Syndrome had very curly, fragile hair, and doctors used a special scalp examination to diagnose him without invasive tests.
210 citations
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February 2008 in “Nature genetics” Mutations in the P2RY5 gene cause autosomal recessive woolly hair.
6 citations
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February 2016 in “American Journal of Dermatopathology” The boy with woolly hair nevus had thinner hair and abnormal hair follicles, which improved with treatment but worsened when treatment stopped.
May 2024 in “Frontiers in medicine” A genetic mutation in the LIPH gene causes tightly curled hair that stops growing in some Japanese individuals.
November 2025 in “Skin Health and Disease” Autosomal recessive woolly hair is rare and involves tightly coiled hair without other health issues.
9 citations
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July 2018 in “Acta biomaterialia” Eyelash curvature is linked to the thickness of the cuticle layer at the root.
27 citations
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January 2010 in “Animal” South American camelids should be sheared early, fleece type affects fiber quality, and the S/P follicle ratio doesn't distinguish between Bolivian llama genotypes.
February 2019 in “bioRxiv (Cold Spring Harbor Laboratory)” The gene Prss53 affects hair shape and bone development in rabbits.
29 citations
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July 2015 in “Journal of Medical Genetics” A genetic variant in the KRT25 gene causes tightly curled hair.
May 2010 in “Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature” A mutation in the KRT74 gene causes woolly hair by affecting hair texture.
May 2010 in “Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature” A mutation in the KRT74 gene causes woolly hair by affecting hair texture.
The curly mutation in SELH/Bc mice affects hair and may help study human genetic disorders.
22 citations
,
January 1985 Water makes hair more flexible, especially the outer layer.
May 2023 in “Accounts of chemical research” New methods can better classify curly hair types and lead to improved hair care products.
35 citations
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September 2003 in “Archives of dermatology” Tiger tail bands in hair are caused by wavy hair fibers with melanin, unlike straight fibers in normal hair.
95 citations
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October 2007 in “International Journal of Dermatology” A new method accurately classifies hair types, showing global hair diversity.
116 citations
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January 1957 in “Australian Journal of Agricultural Research” Certain hair follicle traits in Merino sheep may be inherited.
97 citations
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March 2010 in “The American Journal of Human Genetics” A mutation in the KRT74 gene causes tightly curled hair.
September 2016 in “Journal of dermatological science” The conclusion is that the variation in hair thinness in patients is mostly due to the amount of underdeveloped hairs, and treatments that thicken fine hairs might work for those with mild to severe conditions.
January 2024 in “Indian Journal of Pharmaceutical Sciences” Relaxing certain muscles might straighten curly hair.