Woolly hair is a rare condition.
Uncombable hair syndrome.
Symptoms Hair: difficult to brush, tight locks, short, lighter color.
Usual onset Birth, infancy
Types Familial, hereditary, woolly hair nevus
Risk factors May run in families
Diagnostic method Microscopy, trichoscopy, dermoscopy, electron microscopy
Prognosis May improve with age
Frequency Rare
It has extreme curls and kinks, occurs in non-black people and is distinct from afro-textured hair.
The hairs come together to form tight locks, unlike in afro-textured hair, where the hairs remain individual.
Woolly hair can be generalised over the whole scalp.
Woolly hair tends to run in families, or it may involve just part of the scalp as in woolly hair nevus.
The presence of woolly hair may indicate other problems such as with the heart in Naxos–Carvajal syndrome.
Diagnosis is suspected by its general appearance.
Diagnosis Can be confirmed by scanning electron microscopy.
Described a dominant inheritance in several members with thick skin of palms and soles, curly hair, and two different colored eyes.
Hereditary woolly hair is autosomal dominant.
Familial woolly hair is autosomal recessive process.
Woolly hair be part of the Naxos syndrome, due to passing on of mutations in the JUP gene.
When part of Carvajal syndrome, it is due the passing of mutations of the Desmoplakin gene.
The two syndromes caused by two different genes, are considered as one entity; Naxos–Carvajal syndrome.
The woolly hair of a woolly hair nevus is in a circumscribed area of the scalp, appears in infancy and does not run in families.
The hairs come together to form tight locks, whereas in afro-textured hair the hairs remain individual.
The hairs typically remain shorter than 12 centimetres (4.7 in) and may be slightly lighter in colour.
Woolly hair nevus is a localized area of woolly hair.
Half of people with woolly hair nevus have a warty skin lesion on the same side of the body.
It may be associated with eye problems such as two different colored eyes or strands of tissue across the pupil of the eye, ear problems, kidney disease, tooth decay, impairment of bone growth, and skin lesions.
Generalized woolly hair is typically seen in Naxos–Carvajal syndrome, Noonan syndrome, and cardiofaciocutaneous syndrome.
Diagnosis is suspected by its general appearance and confirmed by scanning electron microscopy.
Microscopy, trichoscopy and dermoscopy also are helpful.
The hair strand typically has a smaller diameter, is ovoid on cross-section and exhibits abnormal twisting, the hair shaft also has weak points and alternating dark and light bands.
Woolly hair is a hair shaft anomaly characterized by tightly curled hair that is often fine and may be associated with hypotrichosis, which is a condition of sparse hair growth.
The condition may improve in adulthood.
Autosomal recessive woolly hair is caused by mutations in several genes, including lysophosphatidic acid receptor 6 (LPAR6), lipase H (LIPH), and keratin 25 (KRT25).
These gene mutations disrupt normal hair follicle development and hair growth, leading to the characteristic tightly curled hair.
In some cases, woolly hair is also associated with other conditions such as hypotrichosis, where the hair is not only curly but also sparse and fragile.
Autosomal dominant woolly hair (ADWH) can be caused by mutations in the keratin K74 (KRT74) gene, among others.
These mutations affect the structural integrity of the hair shaft, leading to the woolly hair phenotype.