A very rare disorder characterized by patches of hair loss involving the scalp, armpits, eyebrows and genitals. The hair loss on the scalp is accompanied by scarring of the skin. Hair follicles become eruptive and spiny usually months to years after hair loss.
Late infantile neuronal ceroid lipofuscinosis (also known as LINCL, Jansky-Bielschowsky and late infantile CLN2/TPP1 disorder) is part of a group of progressive degenerative neurometabolic disorders known as the ceroid lipofuscinosis neuronal (CLNs). The CLNs are characterized by an abnormal accumulation of lipopigments, which are substances made up of fats and proteins within the brain’s nerve cells, eyes, skin, muscle, and other tissues throughout the body. CLN2 causes nerve cells, found in the brain, retina, and central nervous system, to die. Symptoms typically begin between ages 2 and 4. Early signs may include loss of muscle coordination (ataxia) and seizures that do not respond to drugs. This form progresses rapidly and ends in death between ages 8 and 12. The condition is caused by mutations in the CLN 2 gene which lead to deficient activity of the TPP1 enzyme.
Late-onset congenital adrenal hyperplasia is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that Late-onset congenital adrenal hyperplasia, or a subtype of Late-onset congenital adrenal hyperplasia, affects less than 200,000 people in the US population.
A very rare syndrome characterized involving the absence of the whole or part of an arm or leg as well as a severe defect of the abdominal wall. Death often occurs at birth.
A rare syndrome characterized mainly by lateral meningoceles (openings in the spinal cord on the inside of the spine) as well as craniofacial anomalies. The syndrome is believed to involve the abnormal development of the spinal cord, cerebellum and cerebral cortex.
A rare familial syndrome characterized by various internal and external ear abnormalities.
A very rare dominantly inherited disorder that occurs during embryonic development, the earliest stage of pregnancy. Various internal organs or parts of organs can develop in the wrong position in the body.
very rare disorder where an enzyme (sterol C5-desaturase) deficiency prevents the normal synthesis of cholesterol in the body. The deficiency causes various malformations, mental retardation and liver disease .
A genetic eye disorder where the cornea of the eye develops abnormal, lattice-shaped lines caused by abnormal deposits of a substance called amyloid. There are three different types of corneal dystrophy: type 1 is a dominantly inherited form with an early onset of vision impairment, type 2 is a less severe eye disorder but involves systemic amyloidosis and type 3 is a recessive form that usually starts after the age of 70.
A rare skin abnormality involving flat pigmentated patches of skin on the lips and inside mouth as well as black streaky lines on the nails.
A benign condition characterized by the development of lumps in the lymph nodes, especially in the neck, armpits and groin.
A rare disorder characterized by a congenital heart defect, broad big toes, extra little finger and intestinal dysfunction.
Laurin-Sandrow syndrome is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that Laurin-Sandrow syndrome, or a subtype of Laurin-Sandrow syndrome, affects less than 200,000 people in the US population.
Ophanet, a consortium of European partners, currently defines a condition rare when if affects 1 person per 2,000. They list Lbwd syndrome as a "rare disease".
A rare inherited genetic condition where the body is unable to convert certain fats to energy i.e. there is not enough of a certain enzyme (3-hydroxyacyl-coenzyme A dehydrogenase) which is needed to metabolize a type of fat called long-chain fatty acids. The build-up of these fatty acids in the body causes damage.
LCHAD defiency (Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency), is a rare autosomal recessive fatty acid oxidation disorder that prevents the body from converting certain fats into energy. This can become life-threatening, particularly during periods of fasting.
A very rare syndrome characterized mainly by a large head, short arms and clubfoot.
A rare syndrome characterized mainly by fused finger and toe joints as well as other hand and foot anomalies.
Leber congenital amaurosis (LCA) is an eye disorder that primarily affects the retina which is the specialized tissue at the back of the eye that detects light and color. People with this condition typically have severe visual impairment beginning in infancy. The visual impairment tends to be stable, although it may worsen very slowly over time.
Other features include photophobia, involuntary movements of the eyes (nystagmus), and extreme farsightedness. The pupils also do not react normally to light (photophobia), involuntary movements of the eyes (nystagmus), and extreme farsightedness (hyperopia).
The pupils, which usually expand and contract in response to the amount of light entering the eye, do not react normally to light. Instead, they expand and contract more slowly than normal, or they may not respond to light at all. Additionally, the clear front covering of the eye (the cornea) may be cone-shaped and abnormally thin, a condition known as keratoconus.
A specific behavior called Franceschetti's oculo-digital sign is characteristic of Leber congenital amaurosis. This sign consists of poking, pressing, and rubbing the eyes with a knuckle or finger. Researchers suspect that this behavior may contribute to deep-set eyes and keratoconus in affected children.
In rare cases, delayed development and intellectual disability have been reported in people with the features of Leber congenital amaurosis. However, researchers are uncertain whether these individuals actually have Leber congenital amaurosis or another syndrome with similar signs and symptoms.
At least 13 types of Leber congenital amaurosis have been described. The types are distinguished by their genetic cause, patterns of vision loss, and related eye abnormalities.
Leber congenital amaurosis can result from mutations in at least 14 genes, all of which are necessary for normal vision. These genes play a variety of roles in the development and function of the retina. For example, some of the genes associated with this disorder are necessary for the normal development of light-detecting cells called photoreceptors. Other genes are involved in phototransduction, the process by which light entering the eye is converted into electrical signals that are transmitted to the brain. Still other genes play a role in the function of cilia, which are microscopic finger-like projections that stick out from the surface of many types of cells. Cilia are necessary for the perception of several types of sensory input, including vision.
Mutations in any of the genes associated with Leber congenital amaurosis disrupt the development and function of the retina, resulting in early vision loss. Mutations in the CEP290, CRB1, GUCY2D, and RPE65 genes are the most common causes of the disorder, while mutations in the other genes generally account for a smaller percentage of cases. In about 30 percent of all people with Leber congenital amaurosis, the cause of the disorder is unknown.
A rare inherited retinal disease (retinal dystrophy) that starts during the fetal stage. Vision impairment is obvious at birth or within months of birth. Type I is distinguished from the other forms of this condition by the genetic origin of the defect - chromosome 17p13.1, RETGC1 gene.
Leber congenital amaurosis 2 (LCA2) ia a rare inherited retinal disease (retinal dystrophy) that starts during the fetal stage. Vision impairment is obvious at birth or within months of birth. Type 2 is distinguished from the other forms of this condition by the genetic origin of the defect - chromosome 1, RPE65 gene.
Leber congenital amaurosis 3 (LCA3) is a rare inherited retinal disease (retinal dystrophy) that starts during the fetal stage. Vision impairment is obvious at birth or within months of birth. Type 3 is distinguished from the other forms of this condition by the genetic origin of the defect - chromosome 14q23.3, RDH12 gene.
Leber congenital amaurosis 4 (LCA4) is a rare inherited retinal disease (retinal dystrophy) that starts during the fetal stage. Vision impairment is obvious at birth or within months of birth. Type 4 is distinguished from the other forms of this condition by the genetic origin of the defect - chromosome 17p13.1, AIPL1 gene.
Leber congenital amaurosis 5 (LCA5) is a rare inherited retinal disease (retinal dystrophy) that starts during the fetal stage. Vision impairment is obvious at birth or within months of birth. Type 5 is distinguished from the other forms of this condition by the genetic origin of the defect - chromosome 6q11-q16.
Leber congenital amaurosis 9 (LCA9) is a rare inherited retinal disease (retinal dystrophy) that starts during the fetal stage. Vision impairment is obvious at birth or within months of birth. Type 9 is distinguished from the other forms of this condition by the genetic origin of the defect - chromosome 1p36.
Leber's hereditary optic neuropathy (LHON) is a mitochondrially inherited (transmitted from mother to offspring) degeneration of retinal ganglion cells (RGCs) and their axons that leads to an acute or subacute loss of central vision; this affects predominantly young adult males. However, LHON is only transmitted through the mother as it is primarily due to mutations in the mitochondrial (not nuclear) genome and only the egg contributes mitochondria to the embryo. LHON is usually due to one of three pathogenic mitochondrial DNA (mtDNA) point mutations. These mutations are at nucleotide positions 11778 G to A, 3460 G to A and 14484 T to C, respectively in the ND4, ND1 and ND6 subunit genes of complex I of the oxidative phosphorylation chain in mitochondria. Men cannot pass on the disease to their offspring.
A rare condition characterized by a localized group of dilated blood capillaries and aneurysms in the retina of one eye. It is believed to be a mild form of Coat's disease.