Association of a Marker in the Vitamin D Receptor Gene with Marek's Disease Resistance in Poultry

Abstract

Vitamin D is an important immunomodulator that mediates its effect via a nuclear receptor. In this study, we analyzed 3 uncorrelated genetic markers (tag single nucleotide polymorphisms) in the vitamin D receptor gene for association with Marek's disease (MD) resistance. The database consisted of 400 commercial White Leghorn chickens that had been vaccinated with herpes turkey virus and challenged by intraperitoneal injection of the virulent MD virus RB1B. Viral titers in feather tips were determined at weekly intervals for 8 wk, mortality was recorded, and necropsy analyses preformed on all chickens. The 3 genotypes defined by 1 of the markers were associated with significant differences in the viral load (integration of the viral titer over time; P = 3 x 10(-4)). The effect was additive, with the 2 homozygotes differing by a factor of 2. The ranking of the genotypes by viral load, frequency of MD lesions, mortality, and bursal atrophy were consistent. There was no effect on the tissue distribution of MD lesions. The degree of MD resistance in the 9 genotypes defined by the 3 tag single nucleotide polymorphisms was proportional to the frequency of major histocompatibility complex class II-positive peripheral blood leukocytes that had been previously measured in uninfected chickens in a different database.

1α,25(OH)2 Vitamin D3 Modulates Avian T Lymphocyte Functions without Inducing CTL Unresponsiveness

“…Mice VDR -/- models have been used to demonstrate this interdependent relationship [ 12 – 14 ]. Genetic polymorphism in the VDR gene has been associated with susceptibility to several viral infections in human; Dengue Virus (DENV; rs2228570) [ 15 ], Hepatitis B Virus (HBV; FokI C>T) [ 16 ], Respiratory Syncytial Virus (RSV; rs10735810) [ 17 ] and even in chickens; Marek’s Disease Virus (MDV; S1P4) [ 18 ]. In humans, Vitamin D has been shown to be effective in the prevention and control of viral diseases such as Human Immunodeficiency Virus (HIV) [ 19 , 20 ] and RSV [ 21 ].…”

Genome-Wide Identification and Quantification of cis- and trans-Regulated Genes Responding to Marek’s Disease Virus Infection via Analysis of Allele-Specific Expression

“…A number of quantitative trait loci (QTL) associated with MD resistance have been reported outside of the MHC in various lines and breeds of chicken (Vallejo et al, 1998; Yonash et al, 1999; McElroy et al, 2005; Cheng et al, 2008; Heifetz et al, 2009). Nonetheless, like many other quantitative traits, only a very small number of genes have been identified that confer MD resistance (Liu et al, 2001b, 2003; Niikura et al, 2007; Praslickova et al, 2008), and from these, only a fraction of the phenotypic variance has been accounted for potentially due to small effect size, large type 1 error rates, and low LD or different phase between markers and quantitative trait nucleotides (QTN) (Goddard and Hayes, 2009; Manolio et al, 2009). Therefore, utilization of these regions in marker-assisted selection programs has been limited.…”

Mapping QTL affecting resistance to Marek's disease in an F6 advanced intercross population of commercial layer chickens

“…Previous studies in commercial and non-commercial White Leghorn populations have identified genes, QTL and genomic regions associated with resistance to MD (briefly summarized in [ 18 ]; see also [ 19 ]). Heifetz et al [ 18 ], using selective DNA pooling, identified 15 QTL affecting MD resistance in a large reciprocal backcross (BC) between two partially inbred commercial White Leghorn layer chicken lines that differed in resistance to MD.…”