Ocular albinism

Medical condition

Ocular albinism
Specialty	Endocrinology

Ocular albinism is a form of albinism which, in contrast to oculocutaneous albinism, presents primarily in the eyes.^[1] There are multiple forms of ocular albinism, which are clinically similar.^[2]^: 865

Both known genes are on the X chromosome. When the term "autosomal recessive ocular albinism" ("AROA") is used, it usually refers to mild variants of oculocutaneous albinism rather than ocular albinism, which is X-linked.^[3]

Types

Name	OMIM	Gene	Description
Ocular albinism, type 1 (OA1)	300500	GPR143	Also known as Nettleship–Falls syndrome,^[4]^[5]^[6] is the most common variety of ocular albinism. OA1 is usually associated with nystagmus, and difficult to otherwise detect in females; males show more readily observable symptoms.
Ocular albinism, type 2 (OA2)	300600	CACNA1F^[7]	Also known as Forsius–Eriksson syndrome^[8]^[9] or "Åland eye disease", mostly affects males, though females are often carriers and can sometimes be symptomatic; it is frequently linked with protanopic dichromacy (a form of color blindness) and with night blindness (nyctalopia).
Ocular albinism with sensorineural deafness (OASD)	300650	? (Xp22.3)	Is, as its name implies, associated with loss of hearing. May be the same as OA1.^[10]

References

^ "Ocular albinism - Genetics Home Reference".
^ James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology. (10th ed.). Saunders. ISBN 0-7216-2921-0.
^ Hutton SM, Spritz RA (March 2008). "A comprehensive genetic study of autosomal recessive ocular albinism in Caucasian patients". Invest. Ophthalmol. Vis. Sci. 49 (3): 868–72. doi:10.1167/iovs.07-0791. PMID 18326704.
^ synd/990 at Who Named It?
^ E. Nettleship. On some hereditary diseases of the eye. Transactions of the Ophthalmological Societies of the United Kingdom, 1908-1909, 29: 57-198.
^ H. F. Falls. Sex-linked ocular albinism displaying typical fundal changes in the female heterozygote. American Journal of Ophthalmology, Chicago, 1951, 34: 41-50.
^ Jalkanen R, Bech-Hansen NT, Tobias R, et al. (June 2007). "A novel CACNA1F gene mutation causes Aland Island eye disease". Invest. Ophthalmol. Vis. Sci. 48 (6): 2498–502. doi:10.1167/iovs.06-1103. PMID 17525176.
^ synd/1336 at Who Named It?
^ Forsius H, Eriksson AW (April 1964). "[A new eye syndrome with X-chromosomal transmission. a family clan with fundus albinism, fovea hypoplasia, nystagmus, myopia, astigmatism and dyschromatopsia.]". Klin Monatsbl Augenheilkd (in German). 144: 447–57. PMID 14230113.
^ Winship IM, Babaya M, Ramesar RS (November 1993). "X-linked ocular albinism and sensorineural deafness: linkage to Xp22.3". Genomics. 18 (2): 444–5. doi:10.1006/geno.1993.1495. PMID 8288253.

External links

Classification	D ICD-10: E70.3 ICD-10-CM: E70.31 ICD-9-CM: 270.2 MeSH: D016117
External resources	Orphanet: 284804

GeneReviews/NCBI/NIH/UW entry on Ocular Albinism, X-Linked

Inborn error of amino acid metabolism

K→acetyl-CoA

Lysine/straight chain	Glutaric acidemia type 1 type 2 Hyperlysinemia Pipecolic acidemia Saccharopinuria
Leucine	3-hydroxy-3-methylglutaryl-CoA lyase deficiency 3-Methylcrotonyl-CoA carboxylase deficiency 3-Methylglutaconic aciduria 1 Isovaleric acidemia Maple syrup urine disease
Tryptophan	Hypertryptophanemia

G→pyruvate→citrate

Glycine	D-Glyceric acidemia Glutathione synthetase deficiency Sarcosinemia Glycine→Creatine: GAMT deficiency Glycine encephalopathy

G→glutamate→
α-ketoglutarate

Histidine	Carnosinemia Histidinemia Urocanic aciduria
Proline	Hyperprolinemia Prolidase deficiency
Glutamate/glutamine	SSADHD

G→propionyl-CoA→
succinyl-CoA

Valine	Hypervalinemia Isobutyryl-CoA dehydrogenase deficiency Maple syrup urine disease
Isoleucine	2-Methylbutyryl-CoA dehydrogenase deficiency Beta-ketothiolase deficiency Maple syrup urine disease
Methionine	Cystathioninuria Homocystinuria Hypermethioninemia
General BC/OA	Methylmalonic acidemia Methylmalonyl-CoA mutase deficiency Propionic acidemia

G→fumarate

Phenylalanine/tyrosine

Phenylketonuria	6-Pyruvoyltetrahydropterin synthase deficiency Tetrahydrobiopterin deficiency
Tyrosinemia	Alkaptonuria/Ochronosis Tyrosinemia type I Tyrosinemia type II Tyrosinemia type III/Hawkinsinuria
Tyrosine→Melanin	Albinism: Ocular albinism (1) Oculocutaneous albinism (Hermansky–Pudlak syndrome) Waardenburg syndrome
Tyrosine→Norepinephrine	Dopamine beta hydroxylase deficiency reverse: Brunner syndrome

G→oxaloacetate

Urea cycle/Hyperammonemia (arginine aspartate)	Argininemia Argininosuccinic aciduria Carbamoyl phosphate synthetase I deficiency Citrullinemia N-Acetylglutamate synthase deficiency Ornithine transcarbamylase deficiency/translocase deficiency

Transport/
IE of RTT

Other

Pigmentation disorders/Dyschromia

Hypo-/
leucism

Loss of
melanocytes

Vitiligo	Quadrichrome vitiligo Vitiligo ponctué
Syndromic	Alezzandrini syndrome Vogt–Koyanagi–Harada syndrome
Melanocyte development	Piebaldism Waardenburg syndrome Tietz syndrome

Loss of melanin/
amelanism

Albinism	Oculocutaneous albinism Ocular albinism in humans
Melanosome transfer	Hermansky–Pudlak syndrome Chédiak–Higashi syndrome Griscelli syndrome Elejalde syndrome Griscelli syndrome type 2 Griscelli syndrome type 3
Other	Cross syndrome ABCD syndrome Albinism–deafness syndrome Idiopathic guttate hypomelanosis Phylloid hypomelanosis Progressive macular hypomelanosis

Leukoderma w/o
hypomelanosis

Ungrouped

Hyper-

Melanin/
Melanosis/
Melanism

Reticulated	Dermatopathia pigmentosa reticularis Pigmentatio reticularis faciei et colli Reticulate acropigmentation of Kitamura Reticular pigmented anomaly of the flexures Naegeli–Franceschetti–Jadassohn syndrome Dyskeratosis congenita X-linked reticulate pigmentary disorder Galli–Galli disease Revesz syndrome
Diffuse/ circumscribed	Lentigo/Lentiginosis: Lentigo simplex Liver spot Centrofacial lentiginosis Generalized lentiginosis Inherited patterned lentiginosis in black persons Ink spot lentigo Lentigo maligna Mucosal lentigines Partial unilateral lentiginosis PUVA lentigines Melasma Erythema dyschromicum perstans Lichen planus pigmentosus Café au lait spot Poikiloderma (Poikiloderma of Civatte Poikiloderma vasculare atrophicans) Riehl melanosis
Linear	Incontinentia pigmenti Scratch dermatitis Shiitake mushroom dermatitis
Other/ ungrouped	Acanthosis nigricans Freckle Familial progressive hyperpigmentation Pallister–Killian syndrome Periorbital hyperpigmentation Photoleukomelanodermatitis of Kobori Postinflammatory hyperpigmentation Transient neonatal pustular melanosis

Other
pigments

Iron	Hemochromatosis Iron metallic discoloration Pigmented purpuric dermatosis Schamberg disease Majocchi's disease Gougerot–Blum syndrome Doucas and Kapetanakis pigmented purpura/Eczematid-like purpura of Doucas and Kapetanakis Lichen aureus Angioma serpiginosum Hemosiderin hyperpigmentation
Other metals	Argyria Chrysiasis Arsenic poisoning Lead poisoning Titanium metallic discoloration
Other	Carotenosis Tar melanosis

Dyschromia

See also

X-linked disorders

X-linked recessive
Immune	Chronic granulomatous disease (CYBB) Wiskott–Aldrich syndrome X-linked severe combined immunodeficiency X-linked agammaglobulinemia Hyper-IgM syndrome type 1 IPEX X-linked lymphoproliferative disease Properdin deficiency
Hematologic	Haemophilia A Haemophilia B X-linked sideroblastic anemia
Endocrine	Androgen insensitivity syndrome/Spinal and bulbar muscular atrophy KAL1 Kallmann syndrome X-linked adrenal hypoplasia congenita
Metabolic	Amino acid: Ornithine transcarbamylase deficiency Oculocerebrorenal syndrome Dyslipidemia: Adrenoleukodystrophy Carbohydrate metabolism: Glucose-6-phosphate dehydrogenase deficiency Pyruvate dehydrogenase deficiency Danon disease/glycogen storage disease Type IIb Lipid storage disorder: Fabry disease Mucopolysaccharidosis: Hunter syndrome Purine–pyrimidine metabolism: Lesch–Nyhan syndrome Mineral: Menkes disease/Occipital horn syndrome
Nervous system	X-linked intellectual disability: Coffin–Lowry syndrome MASA syndrome Alpha-thalassemia mental retardation syndrome PHF8 Eye disorders: Color blindness (red and green, but not blue) Ocular albinism (1) Norrie disease Choroideremia Other: Charcot–Marie–Tooth disease (CMTX2-3) Pelizaeus–Merzbacher disease SMAX2
Skin and related tissue	Dyskeratosis congenita Hypohidrotic ectodermal dysplasia (EDA) X-linked ichthyosis X-linked endothelial corneal dystrophy
Neuromuscular	Becker muscular dystrophy/Duchenne Centronuclear myopathy (MTM1) Conradi–Hünermann syndrome Emery–Dreifuss muscular dystrophy 1
Urologic	Alport syndrome Dent's disease X-linked nephrogenic diabetes insipidus
Bone/tooth	AMELX Amelogenesis imperfecta
No primary system	Barth syndrome McLeod syndrome Smith–Fineman–Myers syndrome Simpson–Golabi–Behmel syndrome Mohr–Tranebjærg syndrome Nasodigitoacoustic syndrome

X-linked dominant
X-linked hypophosphatemia Focal dermal hypoplasia Fragile X syndrome Aicardi syndrome Incontinentia pigmenti Rett syndrome CHILD syndrome Lujan–Fryns syndrome Orofaciodigital syndrome 1 Craniofrontonasal dysplasia

Diseases of ion channels

Calcium channel

Voltage-gated	CACNA1A Familial hemiplegic migraine 1 Episodic ataxia 2 Spinocerebellar ataxia type-6 CACNA1C Timothy syndrome Brugada syndrome 3 Long QT syndrome 8 CACNA1F Ocular albinism 2 CSNB2A CACNA1S Hypokalemic periodic paralysis 1 Thyrotoxic periodic paralysis 1 CACNB2 Brugada syndrome 4
Ligand gated	RYR1 Malignant hyperthermia Central core disease RYR2 CPVT1 ARVD2