Carrier frequency of autosomal recessive disorders (BC, BLAD, FXID and CVM) in Holstein cows in Jalisco, Mexico

Overbreeding of dairy cattle from a narrow genetic base has led to undesirable effects and genetic anomalies. Animals are chosen for breeding based on potential yield without taking into account reproductive and health criteria (Cole et al. 2016). Among the most well-known recessive genetic defects in Holstein cattle are complex vertebral malformation (CVM), bovine leukocyte adhesion deficiency (BLAD), factor XI deficiency (FXID), and bovine citrullinemia (BC). These conditions have led to significant drops in production and economic losses (Gholap et al. 2014, Cole et al. 2016). CVM, which is caused by a missense mutation, a single-base transversion of guanine to thymine at position 559 in the gene SLC35A3 on bovine chromosome 3, is characterized by delayed growth, vertebral malformation, and bilateral arthrogryposis leading to premature death in calves (Agerholm et al. 2001, 2004). BLAD is characterized by impaired migration of leukocytes to infection sites and tissue lesions during immune responses (Nasreen et al. 2009). The molecular basis of BLAD is a missense mutation (A to G) at position 383 of the CD18 gene located bovine chromosome 1 (Nagahata 2004). FXID, which is caused by a mutation of FXI gene on bovine chromosome 27, is an insertion of a 76-bp adenine-rich fragment in exon 12. This insertion, composed of an imperfect poly-adenine tract followed by a duplicated region of the normal coding sequence, introduces a premature stop codon, which impairs the synthesis of functional protein (Marron et al. 2004), is associated with excessive bleeding and reproductive problems in Holstein ABSTRACT.Virgen-Méndez A. , Ayala-Valdovinos M.A., Galindo-García J., Sánchez-Chiprés D.R. , Lemus-Flores C. & Duifhuis-Rivera T. 2019. Carrier frequency of autosomal recessive disorders (BC, BLAD, FXID and CVM) in Holstein cows in Jalisco, Mexico. Pesquisa Veterinária Brasileira 39(7):481-484. Departamento de Producción Animal, Centro Universitario de Ciencias Biológicas y Agropecuarias, División de Ciencias Veterinarias, Universidad de Guadalajara, Camino Ramón Padilla Sánchez 2100, Nextipac, Zapopan, Jal. C.P. 44600, Mexico. Tel: 33 36821454; E-mail: manayala@cucba.udg. mx The hereditary autosomal recessive disorders bovine citrullinemia (BC), bovine leukocyte adhesion deficiency (BLAD), factor XI deficiency (FXID), and complex vertebral malformation (CVM) have affected dairy cattle breeding significantly around the world. This study examined the carrier frequency of BC, BLAD, FXID, and CVM autosomal recessive disorders in Bos taurus Holstein cows bred in the Altos Norte region of the state of Jalisco, Mexico. We extracted DNA from 408 random samples of peripheral blood, and then used polymerase chain reaction (PCR) to identify insertion mutations for FXID, and PCR with restriction fragment length polymorphism (PCR-RFLP) for CVM, BC and BLAD. We visualized the PCR products using agarose gel electrophoresis stained with GelRed®. We found that 100% of wild-type (N/N) allele homozygous animals for genes CD18, ASS, and FXI were free of the mutations for BLAD, BC and FXID respectively. For gene SLC35A3 we estimated total carrier frequency of 10.3% and allele frequency of 5%.