Pero los niños con la enfermedad de Tay-Sachs nacen sin una de esas importantes enzimas: la hexosaminidasa A (o HEX-A). Por lo tanto, conforme estas. La enfermedad de Tay-Sachs (ETS) es un trastorno genético mortal. Se genera cuando una sustancia grasa se acumula en el cerebro. Esta acumulación causa . A number sign (#) is used with this entry because Tay-Sachs disease (TSD) is caused by homozygous or compound heterozygous mutation in the alpha subunit.
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OMIM Entry – # – TAY-SACHS DISEASE; TSD
For all other comments, please send your remarks via contact us. Only comments written in English can be processed. GM2 gangliosidosis, variant B or Tay-Sachs disease is marked by accumulation of Tzy gangliosides due to hexosaminidase A deficiency.
Three variants have been described according to age of onset. The infantile form type 1 begins between 3 and 6 months of age.
Tay–Sachs disease – Wikipedia
The earliest sign is an incessant startle response to noise. Psychomotor retardation appears after the age of 8 months with sachw, amaurosis, and megalencephaly. A cherry-red macular spot may be found but is not specific. Muscular weakness progresses and leads to paralysis. The disorder degenerates into a state of decerebration and is fatal during childhood. Enzymatic activity of the hexosaminidase A is enfermedav extremely low or totally absent in leucocytes and cultured in fibroblasts obtained by skin biopsy.
In the juvenile sacgs type 2onset is between ages 2 and 6 with locomotor ataxia, behavioural disorders, and tya loss of intellectual capacities, leading to a state of decerebration and death at around the age of The decrease in hexosaminidase A activity is less pronounced than in the infantile form. The adult or chronic form type 3 may begin around the age of 10, but often the disorder is not diagnosed until adulthood.
Two different clinical forms exist.
The first is similar to atypical Friedreich disease, with spinocerebellar ataxia but no cardiac or osseous signs, such as scoliosis or flat feet. The second is that of juvenile spinal amyotrophy resembling Kugelberg-Welander’s syndrome. Mental capacities and behaviour may or may not be affected.
Hexosaminidase A deficiency is found. The causative gene HEXA encodes the alpha subunit of hexosaminidase A enfermevad is located on chromosome 15 15q Screening of heterozygous individuals is available and recommended in populations at increased risk of this disorder individuals of Ashkenazi Jewish descent. Two variants of the disease have been reported.
In GM2 gangliosidosis, variant B1, clinical signs are identical to those found ttay the juvenile and adult forms of variant B. Hexosaminidase A deficiency can only be detected with a specific artificial substrate, which differs from the one used for the B variant. The enzyme activator required for hydrolysing GM2 is deficient.
The gene encoding this protein is located on chromosome 5 5q Prenatal diagnosis is available and recommended in populations at increased risk of this disorder. There is no efficient treatment for Tay-Sachs disease, but anti-epileptics can be prescribed.
A treatment aimed at inhibiting gangliosides synthesis Miglustat is currently being investigated for the slowly progressive forms. Other search option s Alphabetical list.
Summary and related texts. Check this box if you wish to receive a copy of your message. Disease definition GM2 gangliosidosis, variant B or Tay-Sachs disease is marked by accumulation of G2 gangliosides due to hexosaminidase A deficiency.
Summary Epidemiology The prevalence of the disease is 1 case per live births. Clinical description Three variants have been described according to age of onset. Diagnostic methods Screening of heterozygous individuals is zachs and recommended in populations at increased risk of this disorder individuals of Ashkenazi Jewish descent. Antenatal diagnosis Prenatal diagnosis is available and recommended in populations at increased risk of this disorder.
Genetic counseling Tay-Sachs disease is transmitted as an autosomal recessive trait. Management and treatment There is no efficient treatment for Tay-Sachs disease, but anti-epileptics can be prescribed. Detailed information Article for general public Svenska Additional information Further information on this disease Classification s 5 Gene s 1 Clinical signs and symptoms Publications in PubMed Other website s Health care resources for this disease Expert centres Diagnostic tests Patient organisations 66 Orphan drug s 1.
Specialised Social Services Eurordis directory. The documents contained in this web site are presented enermedad information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.