Genetic disorder characterized by abnormal hair fibers
and mental deficiency.
Sabinas Brittle Hair Syndrome.
Unknown. Affected families have been found only in the remote
village of Sabinas in northern Mexico.
Most likely autosomal recessive inheritance.
Affected families demonstrate parental consanguinity with the occurrence in
siblings of both sexes, both of which support autosomal recessive
Examination of hair fibers demonstrates a
reduction in the cuticular layer and a collapsed cortex. The cystine content
of the hair is reduced, and the copper-to-zinc ratio is increased. No
specific histopathologic changes in the central nervous system have been
Made by clinical appearance and by morphologic and
biochemical abnormalities of hair fibers. Affected newborns may be
identified by persistent scalp hypotrichosis.
Characterized by dry, brittle, fragile hair,
developmental delay, and normal stature. Affected newborns may be identified
by persistent scalp hypotrichosis. In the postpubertal period, individuals
have reduced or virtually absent pubic and axillary hair. Onychodystrophy
was noted in some patients. A variable degree of mental retardation has been described.
The condition may be similar to Pollitt syndrome and Amish
hair-brain syndrome. Both of these syndromes demonstrate autosomal
recessive inheritance, abnormal hair, and associated mental retardation. However, the
exact interrelationship of these three syndromes is unclear.
New research found genetic heterogeneity between Amish-hair-brain syndrome on the one hand
and Politt and Brittle hair deficit syndrome on the other hand.
Obtain a full history of the patient's
neurologic status. Patients may benefit from sedative premedication or, depending on the
severity of their mental retardation, from the presence of the primary
care-giver for induction of anesthesia.
Amish Hair-Brain Syndrome: Inherited syndrome with mild
psychomotor retardation, hypogonadism, short stature, and brittle hair.
Pollitt Syndrome: Inherited syndrome with developmental delay and
Netherton Syndrome: Most likely autosomal recessive transmitted
inborn error of metabolism manifesting as bamboo hair, atopic diathesis,
congenital ichthyosiform erythroderma, and hypogammaglobulinemia.
Arbisser AI, Scott CI, Howell RR, et al: A syndrome manifested by brittle
hair with morphologic and biochemical abnormalities, developmental delay and
normal stature. Birth Defects Orig Artic Ser
Howell RR, Arbisser AI, Parsons DS, et al: The Sabinas syndrome. Am J Hum Genet
Nakabayashi K, Amann D, Ren Y, et al: Identification of CTorf11 (TTDN1)
gene mutations and genetic heterogeneity in nonphotosensitive trichothiodystrophy.
Am J Hum Genet