Caprine β-Mannosidase: Sequencing and Characterization of the cDNA and Identification of the Molecular Defect of Caprine β-Mannosidosis

• Published in: Genomics (San Diego, Calif.) Vol. 37; no. 1; pp. 51 - 56
• Main Authors: Leipprandt, Jeffrey R., Kraemer, Stacey A., Haithcock, Benjamin E., Chen, Hong, Dyme, Joshua L., Cavanagh, Kevin T., Friderici, Karen H., Jones, Margaret Z.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01.10.1996; Elsevier
• Subjects: ADN; Amino Acid Sequence; AMINO ACID SEQUENCES; Animals; ARTIFICIAL INTRODUCTION OF RESTRICTION SITES; Base Sequence; beta-Mannosidase; BIOCHEMISTRY; BIOCHIMIE; Biological and medical sciences; BIOQUIMICA; CAPRIN; CAPRINOS; CARRIERS; CHEMICAL COMPOSITION; Chimera; Classical genetics, quantitative genetics, hybrids; COMPLEMENTARY DNA; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; DELETIONS; DNA; DNA, Complementary; ENSAYO; Female; Fundamental and applied biological sciences. Psychology; GENBANK/U46067; Genetics of eukaryotes. Biological and molecular evolution; GLICOSIDASAS; GLYCOSIDASE; GLYCOSIDASES; GOATS; HETEROCIGOTOS; HETEROZYGOTE; HETEROZYGOTES; HOMOCIGOTOS; HOMOZYGOTE; HOMOZYGOTES; Lysosomal Storage Diseases - diagnosis; Lysosomal Storage Diseases - genetics; Male; Mannosidases - genetics; METABOLIC DISORDERS; METHODE; METHODS; METODOS; MOLECULAR SEQUENCE DATA; MUTACION; MUTATION; NUCLEOTIDE SEQUENCE; PCR; Pedigree; POLYMERASE CHAIN REACTION; Prenatal Diagnosis; PRENATAL SCREENING; SECUENCIA NUCLEOTIDICA; SEQUENCE NUCLEOTIDIQUE; TESTAGE; TESTING; TRASTORNOS METABOLICOS; TROUBLE DU METABOLISME; Vertebrata; Nucleotide sequence; Enzyme; Gene expression; Vertebrata; Mammalia; β-Mannosidase; Complementary DNA; Gene; Glycosidases; Hydrolases; Goat; Artiodactyla; Mutation; O-Glycosidases; Ungulata; Mannosidosis
• ISSN: 0888-7543; 1089-8646
• DOI: 10.1006/geno.1996.0519

The complete sequence of the caprine β-mannosidase cDNA coding region has been determined, and a mutation that is associated with caprine β-mannosidosis has been identified. Reverse transcriptase–polymerase chain reactions were performed using primers based on bovine and, later, goat cDNA sequences to produce an overlapping series of amplicons covering the entire coding region. The composite cDNA codes for an 879-amino-acid peptide that has four potentialN-glycosylation sites. Comparison of the caprine and bovine cDNAs reveals that 96.3% of the nucleotides and 95.2% of the deduced amino acids are identical. A single-base deletion at position 1398 of the coding sequence was identified in the cDNA isolated from a goat affected with β-mannosidosis. This deletion results in a shift in the reading frame and a premature termination of translation, yielding a deduced peptide of 481 amino acids. An assay, developed to determine the presence or absence of this mutation, confirmed that animals affected with β-mannosidosis were homozygous for the mutation and that obligate carriers in a caprine β-mannosidosis colony were heterozygous. This assay accurately distinguished between mutation carrier and noncarrier goats and was used for prenatal diagnosis using DNA collected from fetal fluids. The assay also confirmed chimerism in a goat with an atypically mild β-mannosidosis phenotype. Thus, this application enables assessment of the efficacy of engraftment of hematopoietic stem cells after prenatal transfer from donor sources.