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Trichothiodystrophy 4, nonphotosensitive(TTD4)

MedGen UID:
272036
Concept ID:
C1313961
Disease or Syndrome
Synonyms: AMISH BRITTLE HAIR BRAIN SYNDROME; BIDS SYNDROME; HAIR-BRAIN SYNDROME; Trichothiodystrophy nonphotosensitive
SNOMED CT: Pollitt's syndrome (238736006)
 
Gene (location): MPLKIP (7p14.1)
 
Monarch Initiative: MONDO:0021013
OMIM®: 234050

Definition

Trichothiodystrophy is a rare autosomal recessive disorder in which patients have brittle, sulfur-deficient hair that displays a diagnostic alternating light and dark banding pattern, called 'tiger tail banding,' under polarizing microscopy. TTD patients display a wide variety of clinical features, including cutaneous, neurologic, and growth abnormalities. Common additional clinical features are ichthyosis, intellectual/developmental disabilities, decreased fertility, abnormal characteristics at birth, ocular abnormalities, short stature, and infections. There are both photosensitive and nonphotosensitive forms of the disorder (summary by Faghri et al., 2008). Sabinas brittle hair syndrome (211390) is another form of nonphotosensitive TTD. For a discussion of genetic heterogeneity of trichothiodystrophy, see 601675. [from OMIM]

Additional description

From MedlinePlus Genetics
Trichothiodystrophy, commonly called TTD, is a rare inherited condition that affects many parts of the body. The hallmark of this condition is hair that is sparse and easily broken. 

In people with trichothiodystrophy, tests show that the hair is lacking sulfur-containing proteins that normally gives hair its strength. A cross section of a cut hair shows alternating light and dark banding that has been described as a "tiger tail."

The signs and symptoms of trichothiodystrophy vary widely. Mild cases may involve only the hair. More severe cases also cause delayed development, significant intellectual disability, and recurrent infections; severely affected individuals may survive only into infancy or early childhood.

Mothers of children with trichothiodystrophy may experience problems during pregnancy including pregnancy-induced high blood pressure (preeclampsia) and a related condition called HELLP syndrome that can damage the liver. Babies with trichothiodystrophy are at increased risk of premature birth, low birth weight, and slow growth. Most children with trichothiodystrophy have short stature compared to others their age. 

Intellectual disability and delayed development are common in people with trichothiodystrophy, although most affected individuals are highly social with an outgoing and engaging personality. Some people with trichothiodystrophy have brain abnormalities that can be seen with imaging tests. A common neurological feature of this disorder is impaired myelin production (dysmyelination). Myelin is a fatty substance that insulates nerve cells and promotes the rapid transmission of nerve impulses.

Trichothiodystrophy is also associated with recurrent infections, particularly respiratory infections, which can be life-threatening. People with trichothiodystrophy may have abnormal red blood cells, including red blood cells that are smaller than normal. They may also have elevated levels of a type of hemoglobin called A2, which is a protein found in red blood cells. Other features of trichothiodystrophy can include dry, scaly skin (ichthyosis); abnormalities of the fingernails and toenails; clouding of the lens in both eyes from birth (congenital cataracts); poor coordination; and skeletal abnormalities including degeneration of both hips at an early age.

About half of all people with trichothiodystrophy have a photosensitive form of the disorder, which causes them to be extremely sensitive to ultraviolet (UV) rays from sunlight. They develop a severe sunburn after spending just a few minutes in the sun. However, for reasons that are unclear, they do not develop other sun-related problems such as excessive freckling of the skin or an increased risk of skin cancer. Many people with trichothiodystrophy report that they do not sweat.  https://medlineplus.gov/genetics/condition/trichothiodystrophy

Clinical features

From HPO
Decreased fertility
MedGen UID:
452706
Concept ID:
C0729353
Finding
Ventricular septal defect
MedGen UID:
42366
Concept ID:
C0018818
Congenital Abnormality
A hole between the two bottom chambers (ventricles) of the heart. The defect is centered around the most superior aspect of the ventricular septum.
Growth delay
MedGen UID:
99124
Concept ID:
C0456070
Pathologic Function
A deficiency or slowing down of growth pre- and postnatally.
Macrotia
MedGen UID:
488785
Concept ID:
C0152421
Congenital Abnormality
Median longitudinal ear length greater than two standard deviations above the mean and median ear width greater than two standard deviations above the mean (objective); or, apparent increase in length and width of the pinna (subjective).
Partial agenesis of the corpus callosum
MedGen UID:
98127
Concept ID:
C0431368
Congenital Abnormality
A partial failure of the development of the corpus callosum.
Global developmental delay
MedGen UID:
107838
Concept ID:
C0557874
Finding
A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.
Intellectual disability
MedGen UID:
811461
Concept ID:
C3714756
Mental or Behavioral Dysfunction
Intellectual disability, previously referred to as mental retardation, is characterized by subnormal intellectual functioning that occurs during the developmental period. It is defined by an IQ score below 70.
Cerebral cortical atrophy
MedGen UID:
1646740
Concept ID:
C4551583
Disease or Syndrome
Atrophy of the cortex of the cerebrum.
Retrognathia
MedGen UID:
19766
Concept ID:
C0035353
Congenital Abnormality
An abnormality in which the mandible is mislocalised posteriorly.
Severe muscular hypotonia
MedGen UID:
326544
Concept ID:
C1839630
Finding
A severe degree of muscular hypotonia characterized by markedly reduced muscle tone.
Microcephaly
MedGen UID:
1644158
Concept ID:
C4551563
Finding
Head circumference below 2 standard deviations below the mean for age and gender.
Keratoconjunctivitis sicca
MedGen UID:
9620
Concept ID:
C0022575
Disease or Syndrome
Dryness of the eye related to deficiency of the tear film components (aqueous, mucin, or lipid), lid surface abnormalities, or epithelial abnormalities. Keratoconjunctivitis sicca often results in a scratchy or sandy sensation (foreign body sensation) in the eyes, and may also be associated with itching, inability to produce tears, photosensitivity, redness, pain, and difficulty in moving the eyelids.
Hypoplasia of teeth
MedGen UID:
852449
Concept ID:
C0235357
Congenital Abnormality
Developmental hypoplasia of teeth.
Epicanthus
MedGen UID:
151862
Concept ID:
C0678230
Congenital Abnormality
Epicanthus is a condition in which a fold of skin stretches from the upper to the lower eyelid, partially covering the inner canthus. Usher (1935) noted that epicanthus is a normal finding in the fetus of all races. Epicanthus also occurs in association with hereditary ptosis (110100).
Anteverted nares
MedGen UID:
326648
Concept ID:
C1840077
Finding
Anteriorly-facing nostrils viewed with the head in the Frankfurt horizontal and the eyes of the observer level with the eyes of the subject. This gives the appearance of an upturned nose (upturned nasal tip).
Short nose
MedGen UID:
343052
Concept ID:
C1854114
Finding
Distance from nasion to subnasale more than two standard deviations below the mean, or alternatively, an apparently decreased length from the nasal root to the nasal tip.
Nail dystrophy
MedGen UID:
66368
Concept ID:
C0221260
Disease or Syndrome
Onychodystrophy (nail dystrophy) refers to nail changes apart from changes of the color (nail dyschromia) and involves partial or complete disruption of the various keratinous layers of the nail plate.
Concave nail
MedGen UID:
66369
Concept ID:
C0221261
Finding
The natural longitudinal (posterodistal) convex arch is not present or is inverted.
Trichorrhexis nodosa
MedGen UID:
82668
Concept ID:
C0263485
Disease or Syndrome
Trichorrhexis nodosa is the formation of nodes along the hair shaft through which breakage readily occurs. It is thus a focal defect in the hair fiber that is characterized by thickening or weak points (nodes) that cause the hair to break off easily. The result is defective, abnormally fragile hair.
Brittle hair
MedGen UID:
120480
Concept ID:
C0263490
Disease or Syndrome
Fragile, easily breakable hair, i.e., with reduced tensile strength.
Small nail
MedGen UID:
537942
Concept ID:
C0263523
Finding
A nail that is diminished in length and width, i.e., underdeveloped nail.
Wooly hair
MedGen UID:
87469
Concept ID:
C0343073
Finding
The term wooly hair refers to an abnormal variant of hair that is fine, with tightly coiled curls, and often hypopigmented. Optical microscopy may reveal the presence of tight spirals and a clear diameter reduction as compared with normal hair. Electron microscopy may show flat, oval hair shafts with reduced transversal diameter.
Nail dysplasia
MedGen UID:
331737
Concept ID:
C1834405
Congenital Abnormality
The presence of developmental dysplasia of the nail.
Sparse eyelashes
MedGen UID:
375151
Concept ID:
C1843300
Finding
Decreased density/number of eyelashes.
Abnormality of hair texture
MedGen UID:
869296
Concept ID:
C4023722
Finding
An abnormality of the texture of the hair.
Sparse hair
MedGen UID:
1790211
Concept ID:
C5551005
Finding
Reduced density of hairs.
Microphthalmia
MedGen UID:
10033
Concept ID:
C0026010
Congenital Abnormality
Microphthalmia is an eye abnormality that arises before birth. In this condition, one or both eyeballs are abnormally small. In some affected individuals, the eyeball may appear to be completely missing; however, even in these cases some remaining eye tissue is generally present. Such severe microphthalmia should be distinguished from another condition called anophthalmia, in which no eyeball forms at all. However, the terms anophthalmia and severe microphthalmia are often used interchangeably. Microphthalmia may or may not result in significant vision loss.\n\nPeople with microphthalmia may also have a condition called coloboma. Colobomas are missing pieces of tissue in structures that form the eye. They may appear as notches or gaps in the colored part of the eye called the iris; the retina, which is the specialized light-sensitive tissue that lines the back of the eye; the blood vessel layer under the retina called the choroid; or in the optic nerves, which carry information from the eyes to the brain. Colobomas may be present in one or both eyes and, depending on their size and location, can affect a person's vision.\n\nPeople with microphthalmia may also have other eye abnormalities, including clouding of the lens of the eye (cataract) and a narrowed opening of the eye (narrowed palpebral fissure). Additionally, affected individuals may have an abnormality called microcornea, in which the clear front covering of the eye (cornea) is small and abnormally curved.\n\nBetween one-third and one-half of affected individuals have microphthalmia as part of a syndrome that affects other organs and tissues in the body. These forms of the condition are described as syndromic. When microphthalmia occurs by itself, it is described as nonsyndromic or isolated.
Nystagmus
MedGen UID:
45166
Concept ID:
C0028738
Disease or Syndrome
Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms.
Optic atrophy
MedGen UID:
18180
Concept ID:
C0029124
Disease or Syndrome
Atrophy of the optic nerve. Optic atrophy results from the death of the retinal ganglion cell axons that comprise the optic nerve and manifesting as a pale optic nerve on fundoscopy.
Microcornea
MedGen UID:
78610
Concept ID:
C0266544
Congenital Abnormality
A congenital abnormality of the cornea in which the cornea and the anterior segment of the eye are smaller than normal. The horizontal diameter of the cornea does not reach 10 mm even in adulthood.

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVTrichothiodystrophy 4, nonphotosensitive

Recent clinical studies

Etiology

Strang-Karlsson S, von Willebrand M, Avela K, Wallgren-Pettersson C
Am J Med Genet A 2021 Jun;185(6):1875-1882. Epub 2021 Mar 17 doi: 10.1002/ajmg.a.62168. PMID: 33729667
Corbett MA, Dudding-Byth T, Crock PA, Botta E, Christie LM, Nardo T, Caligiuri G, Hobson L, Boyle J, Mansour A, Friend KL, Crawford J, Jackson G, Vandeleur L, Hackett A, Tarpey P, Stratton MR, Turner G, Gécz J, Field M
J Med Genet 2015 Apr;52(4):269-74. Epub 2015 Jan 22 doi: 10.1136/jmedgenet-2014-102418. PMID: 25612912
Eveno E, Bourre F, Quilliet X, Chevallier-Lagente O, Roza L, Eker AP, Kleijer WJ, Nikaido O, Stefanini M, Hoeijmakers JH
Cancer Res 1995 Oct 1;55(19):4325-32. PMID: 7671243

Diagnosis

Strang-Karlsson S, von Willebrand M, Avela K, Wallgren-Pettersson C
Am J Med Genet A 2021 Jun;185(6):1875-1882. Epub 2021 Mar 17 doi: 10.1002/ajmg.a.62168. PMID: 33729667
La Serna-Infantes J, Pastor MC, Trubnykova M, Velásquez FC, Sotomayor FV, Barriga HA
Eur J Med Genet 2018 Jul;61(7):388-392. Epub 2018 Feb 5 doi: 10.1016/j.ejmg.2018.02.004. PMID: 29421601
Corbett MA, Dudding-Byth T, Crock PA, Botta E, Christie LM, Nardo T, Caligiuri G, Hobson L, Boyle J, Mansour A, Friend KL, Crawford J, Jackson G, Vandeleur L, Hackett A, Tarpey P, Stratton MR, Turner G, Gécz J, Field M
J Med Genet 2015 Apr;52(4):269-74. Epub 2015 Jan 22 doi: 10.1136/jmedgenet-2014-102418. PMID: 25612912

Clinical prediction guides

Corbett MA, Dudding-Byth T, Crock PA, Botta E, Christie LM, Nardo T, Caligiuri G, Hobson L, Boyle J, Mansour A, Friend KL, Crawford J, Jackson G, Vandeleur L, Hackett A, Tarpey P, Stratton MR, Turner G, Gécz J, Field M
J Med Genet 2015 Apr;52(4):269-74. Epub 2015 Jan 22 doi: 10.1136/jmedgenet-2014-102418. PMID: 25612912

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