tailieunhanh - The Gale Genetic Disorders of encyclopedia vol 1 - part 9

Vấn đề với dáng đi có thể tiến triển qua nhiều năm hoặc nhiều thập kỷ trong HSP không biến chứng. Phát hiện này có thể bắt đầu ở bất cứ độ tuổi nào, từ thời thơ ấu đến tuổi trưởng thành muộn. Những vấn đề thường giới hạn ở các chi dưới (chân và bàn chân). | HSP is complicated if other complex problems are present such as seizures dementia loss of muscle mass mental delays dry and thick skin ichthyosis vision problems or loss and ataxia. Problems with gait may progress over years or decades in uncomplicated HSP. This finding may begin at any age from early childhood through late adulthood. The problems are usually limited to the lower extremities legs and feet . Occasionally urinary bladder disturbances may develop over time. People with complicated HSP have other associated health problems including mental delays and dementia. Alternate names for HSP include hereditary spastic paraparesis familial spastic paraplegia familial spastic paralysis and Stumpell-Lorrain syndrome. Genetic profile HSP is a genetically diverse group of disorders. It can be inherited in autosomal dominant or autosomal recessive manners these are further divided into uncomplicated and complicated groups. An X-linked recessive form also exists for complicated HSP. The genes for HSP are designated spastic gait SPG genes and are numbered 1-13 in order of their discovery. Determination of the exact type of HSP in a family is usually done by a detailed family history rather than genetic testing. In autosomal recessive HSP individuals may be carriers meaning that they carry a copy of an altered gene. However carriers often do not usually have symptoms of HSP. Those affected with autosomal recessive HSP have two copies of an altered gene having inherited one copy from their mother and the other from their father. Thus only two carrier parents can have an affected child. For each pregnancy that two carriers have together there is a 25 chance for them to have an affected child regardless of the child s gender. In families with autosomal recessive HSP one would not expect to find other affected family members in past generations. Autosomal recessive uncomplicated HSP is thought to represent about 25 of inherited spastic paraplegia. The SPG5 gene found on .