The Metabolic Genetic Screening Laboratory was the first laboratory devoted to the discovery of hereditary diseases in companion animals and was established at the University of Pennsylvania School of Veterinary Medicine three decades ago. The Transfusion Laboratory was opened two decades ago at Penn when the importance of blood types was being recognized for transfusions as well as feline hemolysis of the newborn. Finally, a decade ago the Josephine Deubler Genetic Disease Testing Laboratory was established based upon our identification of the molecular defects for several hereditary diseases. It is named after Dr. Josephine Deubler, Penn's first female graduate and first female PhD recipient, an AKC judge, and an active show chairman of Bucks County and the Montgomery County Kennel Club. Along with the Pediatric, Genetics and Reproduction Clinic, the labs are part of a clinical service that encompasses genetic screening and counseling for hereditary diseases in companion animals and is generally referred to as PennGen.

Hereditary diseases of companion animals are an important problem for breeders and owners. Nearly 1000 and 200 inherited disorders have been identified in the dog and cat, respectively. The Section of Medical Genetics at the University of Pennsylvania discovered and characterized many hereditary disorders in dogs and cats from the clinical features to the molecular genetic defect. Thereby, the mode of inheritance was determined and hematological, biochemical, and molecular genetic tests were developed to identify affected and carrier animals. The different laboratories of PennGen were established to offer genetic screening to veterinarians, breeders, and pet owners to assist them in their effort to breed animals free of hereditary diseases that were known to occur in their breed.

Since most of the diseases are recessively inherited, tests to identify carriers who are clinically asymptomatic but can pass on the defective (mutant) gene have been developed. Several DNA-based tests, which represent the most accurate screening tests, have been introduced by PennGen and are listed below. Some have been shown to be common defects in certain breeds while others seem to occur rarely. Several other genetic testing laboratories are also offering these mutation tests discovered by Penn.

Inherited metabolic diseases, which include all biochemical disorders caused by genetically determined defects, have gained notable interest during these years. The mission of the Metabolic Genetics Screening Laboratory at Penn is to characterize new diseases in companion animals with signs suspicious for genetic disorders. Genetic metabolic screening includes analyses of amino acids, organic acids, and carbohydrates (glycosaminoglycans and oligosaccharides) of urine and serum samples for various inborn errors of metabolism. These tests can detect a metabolic defect in any breed and thus can be applied to define defects in breeds, where a certain disease has not been previously identified. Disease characterization sometimes requires the examination of special tissue or blood cell samples. Some of the typical clinical signs of inborn errors of metabolism include neonatal death, failure to thrive, growth retardation, corneal clouding, chronic vomiting or diarrhea, anorexia, neurological signs, hepatosplenomegaly, skeletal abnormalities and facial dysmorphia. Any animal showing these signs is a candidate for submission of urine and serum/plasma samples to our laboratory for metabolic screening.

The PennGen laboratory is a non-profit operation under the auspices of the School of Veterinary Medicine at the University of Pennsylvania, is supported by National Institutes of Health and donations from individuals and companion animal organizations (National MPS Society, Inc., the Canine Health Foundation, the Winn Feline Foundation), with modest service fees. Detailed information on testing and sample submission may be found at www.vet.upenn.edu/penngen.

Molecular Genetic Tests offered by PennGen. (www.vet.upenn.edu/penngen for more info)