LABORATORY IDENTIFICATION OF INBORN ERRORS OF METABOLISM

先天性代谢缺陷的实验室鉴定

• 批准号: 7391944
• 负责人: URS GIGER
• 金额: $ 30.22万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7391944
• 关键词: LABORATORY; IDENTIFICATION; INBORN; ERRORS; METABOLISM

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Animals with signs suggestive of an inherited metabolic disease, particularly young animals with failure to thrive, metabolic disturbances, seizures, bone deformities, eye abnormalities (retinopathies, cataracts, corneal clouding), persistent vomiting and chronic diarrhea are screened for qualitative and quantitative changes in the urinary excretion of amino acids, organic acids, carbohydrates, and glycosaminoglycans. Animals with abnormal findings are further investigated by blood and urine determinations using automated amino acid analysis, gas chromatography, electrophoresis, and mass spectrometry to identify and quantify the abnormal metabolites. Defects suspected to be the result of enzymatic blocks are investigated by specific enzyme assays. Family studies and breeding experiments are used to establish the mode of inheritance of defined defects. Light and electron microscopic studies of tissues utilize special stains and immunohistochemistry to identify stored substrates and specific gene products. Since the last report, a total of 783 samples were analyzed in 2004 by metabolic screening from numerous canine and feline breeds as well as from a few ferrets and equine samples. The majority of these samples were urine (412), serum/plasma (181), and EDTA whole blood (113); other samples included tissues such as liver, spleen, kidney, skin, and blood and lymph node smears. Samples were received from 33 states in the United States, Australia, Canada, France, Finland, Italy, Japan, Puerto Rico and the United Kingdom. Individual case diagnoses of diseases previously recognized by the Metabolic Genetic Screening Laboratory included Fanconi Syndrome (25), type I and non-type I cystinuria (11), isolated glucosuria (4), methylmalonic aciduria associated with intestinal cobalamin malabsorption (5), and various storage diseases. In collaboration with the Children?s Hospital of Philadelphia, numerous samples were analyzed by HPLC and gas chromatography for amino acid and organic acid quantitation in order to confirm abnormalities found by paper chromatographic and spot tests. These studies assisted in the identification of companion animals affected with models currently under investigation in the Referral Center (see the various subprojects), including cystinuria in Newfoundlands, Mastiffs, Scottish Deerhounds, Cardigan Welsh Corgis, and domestic shorthair cats, cobalamin malabsorption in Border Collies, Komodor, Australian Shepherds, Cattle Dogs, and Beagles, erythroenzymopathies, hereditary bleeding disorders including von Willebrand disease in Dobermans, hemophilia in German shepherds and various other breeds, fibrinogen deficiency in a mixed breed dog, factor VII deficiency in Beagles, factor XI deficiency in Kerry Blue Terriers, and lysosomal storage diseases (MPS I, IIIB, VI, VII, I-Cell disease, Neimann-Pick C, Krabbe disease, and alpha-mannosidosis). A focus of the Metabolic Genetic Screening Laboratory is the identification of companion animals with novel and previously described lysosomal storage diseases through urine electrophoresis, enzyme assays, and blood smear analysis. (1) Examination of urinary glycosaminoglycans (GAGs) and serum enzyme assays led to the identification of a Himalyan cat with mucopolysaccharidosis VI (MPS VI). Subsequent DNA analysis indicated the deficiency is due to the mutation previously described to cause a severe form of the disease in Siamese cats. (2) After the original discovery of MPS VII deficiency in a mixed breed dog, which led to the intense independently supported studies on the pathophysiology, molecular basis and gene transfer investigations, we have recently found two families of German shepherd dogs with MPS VII due to the same mutation. Additionally, the first case of MPS VII in Rat Terriers was identified. Details of these studies can be found in the subprojects. Recently GAG and enzyme analyses also led to the diagnosis of MPS VII in a male domestic short hair cat. (3) Increased serum activity of lysosomal enzymes, the presence of white blood cell inclusion bodies in the blood smear, and little to no activity of arylsulfatase B in white blood cells also led to the diagnosis of MPS VI in a one year-old Miniature Pincher. In our laboratory we determined the disease-causing mutation in this and the Miniature schnauzer breed, over 50 canines for these breeds have been characterized as normal, carrier, or affected through DNA testing. (4) DNA screening for MPS IIIB in Skipperkes continues and we have examined a total of 1300 Schipperkes resulting in approximately 10% carriers and 1% affected dogs. (5) Other enzyme deficiencies identified included alpha-mannosidosis that was diagnosed in a Persian and one domestic short hair cat and alpha-fucosidosis diagnosed in 3 month-old English Springer Spaniel. The Josephine Deublar Genetic Disease Testing Laboratory has screened over 1000 animals, both canine and feline breeds for Pyruvate Kinase Deficiency (PK) and approximately 80 canines for Phosphofructokinase Deficiency (PFK) among other DNA test offered through the laboratory. Collaborations have been established between various universities to further some the above new findings. 2. ENZYME STUDIES 2004: 2-1. Canine Enzyme Canine Serum White Red Total Blood Cells Alpha-mannosidase 44 3 47 Beta-mannosidase 2 2 4 Beta-glucuronidase 5 1 57 Hexosaminidase 13 13 26 Galactosidase 11 10 21 Alpha-L-iduronidase 3 12 15 Arylsulfatase B 2 18 20 Alpha-fucosidase 39 3 42 Pyruvate Kinase 3 3 Total 170 62 3 235 2-2. Feline Enzyme Feline Serum White Red Total Blood Cells Alpha-mannosidase 32 4 36 Beta-mannosidase 4 1 5 Beta-glucuronidase 33 10 43 Hexosaminidase 7 14 21 Galactosidase 9 11 20 Alpha-L-iduronidase 5 12 17 Arylsulfatase B 6 21 27 Alpha-fucosidase 28 12 40 Pyruvate Kinase 2 2 Total 124 85 2 211