Analysis of differences in prion protein gene (PRNP) polymorphisms between Algerian and Southern Italy's goats

Abstract

Goats are adapted to live in harsh areas of the world ensuring minimum levels of milk and meat production without much economic input. Scrapie is a fatal prion disease of small ruminants detected in different countries worldwide. Polymorphisms in the prion protein gene (PRNP) modify the degree of susceptibility/resistance to scrapie. PRNP polymorphisms were analysed in the four main Algerian goat breeds (Naine de Kabylie, Arbia, Mozabite, Mekatia), and in two native breeds of South Italy (Aspromontana from Calabria and Cilentana from Campania). The results were compared also with two previously described Sicilian native breeds (Girgentana and Rossa Mediterranea). Seven amino acid substitutions were detected in Naine de Kabylie goat which represents the original native Berber breed. All other breeds presented no more than six variants and common polymorphisms were present at codons, 154 and 240. Isoleucine at 137 was present in Algerian breeds only. The Italian Cilentana shared more variants with Algerian breeds whereas the Aspromontana breed was the only one to show a Serine at 127. Exclusive new variants were not detected since all polymorphisms were already described in other goats worldwide. The scrapie protective allele encoding lysine (K) at codon 222 was detected in the Naine de Kabylie and M'zabite breeds at low-frequency whereas is present with frequencies higher than 10% in all the Italian breeds reared in regions with elevated scrapie incidence. The overall results showed a substantial number of polymorphisms in PRNP, particularly in Naine de Kabylie breed, which carried also unique genotypes. ARTICLE HISTORY

Novel Variations at Three Different Positions of Prion Protein Coding Gene in Ethiopian Sheep Breeds and the Resistance/Susceptible Status to Classical and Atypical Scrapie

“…Substitution with a different variant having different physicochemical properties might influence the conformational plasticity of prion protein and my further could tempt the emergence of new scrapie disease form.Similar to previous studies, additional amino acid polymorphic sites i.e. G126A, G126A(heterozygous), G127G, G127V(heterozygous), G127A(heterozygous), S138S, I142IT, N146S, N146S(heterozygous), R231R, and L237L were identified[3][4][5][6]. In the present study, the variant at position 127 was in particular highly polymorphic.…”

“…An earlier study linked genotypes such as AC 151 RQ to prolonged incubation period after scrapie exposure [10]. Together with that, several studies reported polymorphisms such as G126A, G126G, G127G, G127V, G127A, and S138S [3][4][5][6] in sheep prion protein with or without direct effect to susceptibility to scrapie.…”

Novel Variations in Native Ethiopian Goat breeds PRNP Gene and Their Potential Effect on Prion Protein Stability

“…R154H variant was detected at a low frequency in Afar(present study), Western highland, Long Eared Somali, and Aegean region goat breeds 12,26 . R154H variant in the Algerian breed has been reported in 15-26% of the study population 9 . The variant T193I was first reported in a recent study by Vitale M. et al, 2019 at a frequency similar to the current observation 12 .…”

Two novel amino acid substitutions in highly conserved regions of prion protein (PrP) and a high frequency of a scrapie protective variant in native Ethiopian goats

“…The presence of p.(Asn146Ser) in Halep (Damascus), Ethiopian and Tanzanian native goats suggests that the allele was naturally selected in the Middle East first, and spread through the central Sahara and Ethiopia later [35, 36] and subsequently into southern parts of the African continent through a different migration route compared to the main Mediterranean and North African routes. As in the Sicilian Damascus breed, p.(Asn146Ser) has not been detected so far in Algerian, Tunisian and Moroccan goats [37, 38]…”