title: Subfertility and growth restriction in a new galactose-1 phosphate uridylyltransferase (GALT) - deficient mouse model.
abstract: The first GalT gene knockout (KO) mouse model for Classic Galactosemia (OMIM 230400) accumulated some galactose and its metabolites upon galactose challenge, but was seemingly fertile and symptom free. Here we constructed a new GalT gene-trapped mouse model by injecting GalT gene-trapped mouse embryonic stem cells into blastocysts, which were later implanted into pseudo-pregnant females. High percentage GalT gene-trapped chimera obtained were used to generate heterozygous and subsequently, homozygous GalT gene-trapped mice. Biochemical assays confirmed total absence of galactose-1 phosphate uridylyltransferase (GALT) activity in the homozygotes. Although the homozygous GalT gene-trapped females could conceive and give birth when fed with normal chow, they had smaller litter size (P=0.02) and longer time-to-pregnancy (P=0.013) than their wild-type littermates. Follicle-stimulating hormone levels of the mutant female mice were not significantly different from the age-matched, wild-type females, but histological examination of the ovaries revealed fewer follicles in the homozygous mutants (P=0.007). Administration of a high-galactose (40% w/w) diet to lactating homozygous GalT gene-trapped females led to lethality in over 70% of the homozygous GalT gene-trapped pups before weaning. Cerebral edema, abnormal changes in the Purkinje and the outer granular cell layers of the cerebellum, as well as lower blood GSH/GSSG ratio were identified in the galactose-intoxicated pups. Finally, reduced growth was observed in GalT gene-trapped pups fed with normal chow and all pups fed with high-galactose (20% w/w) diet. This new mouse model presents several of the complications of Classic Galactosemia and will be useful to investigate pathogenesis and new therapies.
authors.affiliation: Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Manshu
authors.initials: M
authors.lastname: Tang
authors.affiliation: Department of Pathology, University of Florida, Jacksonville, FL, USA.
authors.forename: Anwer
authors.initials: A
authors.lastname: Siddiqi
authors.affiliation: ARUP Laboratories and Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Witt
authors.affiliation: ARUP Laboratories and Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Yuzyuk
authors.affiliation: Department of Human Genetics, University of Miami School of Medicine, Miami, FL, USA.
authors.forename: Britt
authors.initials: B
authors.lastname: Johnson
authors.affiliation: Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Nisa
authors.initials: N
authors.lastname: Fraser
authors.affiliation: Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Wyman
authors.initials: W
authors.lastname: Chen
authors.affiliation: Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Rafael
authors.initials: R
authors.lastname: Rascon
authors.affiliation: Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Xue
authors.initials: X
authors.lastname: Yin
authors.affiliation: Department of Pathology, University of Florida, Jacksonville, FL, USA.
authors.forename: Harish
authors.initials: H
authors.lastname: Goli
authors.affiliation: Department of Human Genetics, University of Miami School of Medicine, Miami, FL, USA.
authors.forename: Olaf A
authors.initials: OA
authors.lastname: Bodamer
authors.affiliation: Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Kent
authors.initials: K
authors.lastname: Lai
mesh_terms: D000483:Alleles; D000818:Animals; D001921:Brain / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D005690:Galactose / Q000008:administration & dosage / Q000633:toxicity; D005693:Galactosemias / Q000235:genetics*; D060005:Genotyping Techniques; D005978:Glutathione / Q000378:metabolism; D006579:Heterozygote; D006720:Homozygote; D007246:Infertility / Q000235:genetics*; D007774:Lactation / Q000235:genetics; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D005694:UTP-Hexose-1-Phosphate Uridylyltransferase / Q000172:deficiency* / Q000235:genetics* / Q000378:metabolism
chemical_list: D005694:UTP-Hexose-1-Phosphate Uridylyltransferase; D005978:Glutathione; D005690:Galactose