Assignment of the genes for lactate dehydrogenase A and B in the pig to chromosome No. 4 and No. 5 by somatic cell hybrids

Further data on chromosomal assignments of pig enzyme loci LDHA, LDHB, MPI, PEPB and PGM1, using somatic cell hybrids

Clear interspecies differentiation between the chromosomes in pig-mouse somatic cell hybrids was achieved by using the THA-technique for the cytogenetic analysis. The assignments of LDHB and MPI to pig chromosomes nos 5 and 7 respectively, reported previously, were confirmed by analysis of 34 hybrid clones. The LDHA, PEPB and PGM1 genes were assigned to pig chromosomes nos 2, 5 and 6 respectively. Both LDHB and PEPB were indicated to be located on the long arm, except the most proximal part, of pig chromosome no. 5. The proposed synteny between LDHB and PEPB in pigs is in accordance with the synteny observed between these two loci in several other mammalian species.

Localization of the citrate synthase (CS) gene to the p12-p13 bands of chromosome 5 in pigs by in situ hybridization

Citrate synthase (CS) is a key enzyme of the Krebs tricarboxylic acid cycle. A 1.4 kb porcine CS cDNA probe was used to chromosomally localize the CS gene in pigs by in situ hybridization. Two in situ hybridization experiments were conducted. Although the first experiment indicated a distinct signal on the 5p12-p13 bands, a secondary signal was observed on the 13q24-q32 bands. Hence, a second in situ hybridization experiment was conducted at higher stringency. The results demonstrated a consistent signal on the 5p12-p13 bands, and the signal on chromosome 13 was scattered with no prominent secondary peak. The CS gene was therefore assigned to the p12-p13 bands of chromosome 5 in pigs.

The gene for bovine interferon gamma (IFNG) maps to the q22-q24 bands of chromosome 5 in cattle

A approximately 700 bp bovine IFNG cDNA probe was used for the chromosomal localization of the IFNG gene in cattle using in situ hybridization technique. This locus has previously been assigned to chromosome 5 by analysis of a somatic cell hybrid panel. The in situ hybridization results obtained in the present study allow us to map the locus at the 5q22-q24 bands. Relative location of the IFNG gene and the class II cytokeratin and HOX3 gene clusters in cattle and humans is discussed.