Variation in the Toll-like Receptor 4 (TLR4) gene affects milk traits in dairy cows.

The objective of this Research Communication was to use polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) analysis to investigate a region of the bovine TLR4 gene (TLR4) in pasture-fed New Zealand (NZ) Holstein-Friesian × Jersey (HF × J) cross dairy cows and to determine whether gene variation was associated with milk production traits. Genetic variation was observed, with two variants (A and B) containing a single nucleotide polymorphism (SNP) (c.2021C/T) that was non-synonymous and putatively results in a p.Thr674Ile substitution in the transmembrane/cytoplasmic domain of TLR4. Variant A was associated with higher milk yields, but lower milk fat percentages, whereas B was associated with lower milk yields, but higher fat and protein percentages. Cows of genotype AA produced more milk than AB or BB cows, but the milk produced by AA cows contained less fat than AB or BB cows.

Three new mutations account for the prevalence of glucose 6 phosphate deshydrogenase (G6PD) deficiency in Tunisia.

A previous study on G6PD deficiency carried out on Tunisian population, led to the finding of seven different mutations with the prevalence of G6PD A- variant. This present study reports 23 new unrelated deficient subjects studied at the molecular level to determine the mutation that causes G6PD deficiency. Using PCR-SSCP of coding regions followed by direct sequencing of abnormal pattern, three new mutations were detected. Two of them are polymorphic intronic mutations. The first is IVS-V 655C-->C/T, found in four female subjects with mild deficiency of class III variant. The second is IVS-VIII 43 G-->A, found in three male subjects with mild deficiency of class III variant. The third mutation is in the exon region so that it changes the primary structure of the molecule. It is cited for the first time and named G6PD Tunisia. This variant affects the exon 7 of the gene at genomic position 15435 G→T. Its cDNA position is 93 G→G/T, it changes arg 246 to leu. This mutation was found in one heterozygote female with deficiency of class II who have had hemolytic anemia due to ingestion of fava beans. Finally, G6PD Med variant, reported before in three cases, was also found in five other cases (four heterozygote females and one male hemizygote). These findings first enlarge the spectre of mutations to be ten variant mutations, characterizing the Tunisian population and also contribute with hemoglobin gene research in our laboratory to trace the whole genetic map of Tunisian population.

Molecular cloning, expression and association study with reproductive traits of the duck LRP8 gene.

1. Two splice variants of duck LRP8 were identified, one containing 8 ligand-binding repeats (LRP8-1) and the other containing only 7 repeats (LRP8-2). The two transcripts share ~71-91% nucleic acid identity and ~65-94% amino acid identity with their counterparts in other species. A phylogenetic tree based on amino acid sequences shows that duck LRP8 proteins are closely related to those of chicken, turkey and zebra finch. 2. The semi-quantitative reverse transcription polymerase chain reaction (RT-PCR )analysis indicates that the two transcripts are expressed in all the examined tissues, and the LRP8-1 transcript is more highly expressed in hypothalamus, ovary and pituitary gland than in other detected tissues. 3. Six single nucleotide polymorphisms (SNPs) were identified in the coding region. Association analysis demonstrated that the c.528C > T genotypes were associated with egg production (EP) (EP210d, EP300d and EP360d), age at laying the first egg (AFE) and body weight at sexual maturity (BWSM). The c.1371A > G genotypes were associated with egg production (EP210d, EP300d and EP360d). 4. The haplotypes of c.528C > T and c.1371A > G were associated with EP (EP210d, EP300d and EP360d), yolk weight (YW), albumen weight (AW), egg weight (EW), BWSM and the first egg weight (FEW). 5. Duck LRP8 gene was associated with some reproductive traits and is an important candidate gene for the genetic selection of improved reproductive traits.

Mucopolysaccharidosis IVA within Tunisian patients: Confirmation of the two novel GALNS gene mutations.

UNLABELLED: Mucopolysaccharidosis type IVA or Morquio A disease is an autosomal recessive disease resulting from a deficiency of the lysosomal enzyme N-acetylgalactosamine-6-sulfate-sulfatase, which hydrolyses N-acetylgalactosamine-6-sulfate and galactose-6-sulfate in glycosaminoglycans. Phenotypes in Morquio A disease vary from the classical form with severe bone dysplasia, heart valve involvement, corneal opacity, short trunk dwarfism and a life span of 20 to 30 years, to attenuated forms with normal life span, mild bone involvement and mild visceral organ involvement. Unlike the other forms of mucopolysaccharidoses, Morquio A disease is characterized by normal intelligence. AIM OF THE STUDY: The aims of this study were to determine if the novel GALNS anomalies IVS1+1G-A and G66R identified in Tunisia are mutations or polymorphisms. PATIENTS AND METHODS: This study was carried out on six Morquio A patients recruited from many regions of Tunisia. We have used SCCP, sequencing and enzymatic digestion. RESULTS: IVS1+1G-A and G66R were two deleterious mutations and not polymorphisms. CONCLUSION: Screening of mutations and polymorphisms in GALNS gene provide useful information on genotype/phenotype correlations. It should also facilitate more accurate genetic counselling of newly diagnosed cases and their family members.

Polymorphism in exons of the myostatin gene and its relationship with body weight traits in the Bian chicken.

In our research, single nucleotide polymorphisms (SNPs) of exon regions of the myostatin gene were detected by PCR-SSCP in the Bian chicken and three reference chicken populations (Jinghai, Youxi, and Arbor Acre). Four novel SNPs (G2283A, C7552T, C7638T, and T7661A) were detected. The findings from the least square means showed that Bian chickens with EE and DE genotypes had significantly higher body weight, at 6-18 weeks of age, than those of the DD genotype (P < 0.05). The results suggest that the mutation G2283A, detected in exon 1, has potential as a genetic marker for body weight traits in the Bian chicken.

Nucleotide variability of protamine genes influencing bull sperm motility variables.

Protamines (PRMs), important proteins of chromatin condensation in spermiogenesis, are promising candidate genes to explore markers of sperm motility. The coding and in-silico predicted promoter regions of these genes were investigated in 102 crossbred and 32 purebred cattle. Also, mRNA quantification was done to explore its possibility as diagnostic tool of infertility. The PCR-SSCP analysis indicated there were two band patterns only in fragment I of the PRM1 and fragment II of the PRM2 gene. The sequence analysis revealed A152G and G179A transitions in the PRM1 gene. Similarly, G35A, A49G and A64G transitions were identified in the PRM2 gene which resulted in altered amino acid sequences from arginine (R) to glutamine (Q), from arginine (R) to glycine (G) and from arginine (R) to glycine (G), respectively. This caused the reduction in molecular weight of PRM2 from 2157.66 to 1931.33 Da due to reduction in the number of basic amino acids. These altered properties of the PRM2 protein led to the reduction in Mass Motility (MM: P < 0.01), Initial Progressive Motility (IPM; P < 0.05) and Post Thaw Motility (PTM; P < 0.05) in crossbred bulls. The least squares analysis of variance indicated there was an effect of PRM2 haplotypes on MM (P = 0.0069), IPM (P = 0.0306) and PTM (P = 0.0500) in crossbred cattle and on PTM (P = 0.0408) in the overall cattle population. Based on the RT-qPCR analysis, however, there was not any significant variation of PRM1 and PRM2 gene expression among sperm of Vrindavani bulls with relatively lesser and greater sperm motility.

Novel polymorphisms of the IGF1R gene and their association with average daily gain in Egyptian buffalo (Bubalus bubalis).

The objective of this study was to detect insulin-like growth factor 1 receptor (IGF1R) polymorphisms, their allele, and genotype frequencies and to determine associations between these polymorphisms and growth traits in Egyptian water buffalo. Three loci of the IGF1R coding region were amplified by RT-PCR and, subsequently, subjected to sequence analysis, followed by single-strand conformation polymorphism to identify different allelic patterns. A total of 11 novel polymorphisms were detected; 6 SNPs among Egyptian water buffaloes and 5 polymorphisms compared with Indian buffalo (Y12700). Three of those polymorphisms; GAG Indel polymorphism, C261G, and G263C SNPs, were nonsynonymous mutations. The GAG Indel polymorphism led to deletion of E (glutamic) amino acid (aa) in the IGF1R of Egyptian water buffaloes compared with Indian buffalo. However, C261G SNP, which replaced A (alanine) by G (glycine) aa, and G263C SNP, which changed A (alanine) to P (proline) aa, were detected among Egyptian water buffaloes. Three different single-strand conformation polymorphism patterns were observed in exon 21: CC/CC, GG/GG, and CG/GC with frequencies of 0.291, 0.253, and 0.556, respectively. The heterozygous animals (CG/GC) had a higher ADG than homozygous animals (CC/CC and GG/GG) from birth to 6 mo of age. We conclude that the heterozygous haplotype, C261G/G263C, in exon 21 of the IGF1R gene is associated with the ADG during the early stages of life (from birth to 6 mo of age) and could be used as a genetic marker for selection of growth traits in Egyptian buffalo.

The natural history of OPA1-related autosomal dominant optic atrophy.

BACKGROUND/AIMS: Autosomal dominant optic atrophy (ADOA) is a genetically heterogenous disease. However, a large proportion of this disease is accounted for by mutations in OPA1. The aim of this longitudinal study was to investigate disease progression in Australian ADOA patients with confirmed OPA1 mutations. METHODS: Probands with characteristic clinical findings of ADOA were screened for OPA1 mutations, and relatives of identified mutation carriers were invited to participate. Disease progression was determined by sequential examination or using historical records over a mean of 9.6 (range 1-42) years. RESULTS: OPA1 mutation carriers (n = 158) were identified in 11 ADOA pedigrees. Sixty-nine mutation carriers were available for longitudinal follow-up. Using the right eye as the default, best-corrected visual acuity (BCVAR) remained unchanged (defined as visual acuity at or within one line of original measurement) in 43 patients (62%). BCVAR worsened by 2 lines in 13 patients (19%). BCVAR deteriorated by more than 2 lines in six patients (9%). Ten per cent of patients had an improvement in visual acuity. Mean time to follow-up was 9.6 years with the mean visual acuity being 6/18 for both the initial and subsequent measurements. There was no statistical significance in the rate of BCVAR loss across different OPA1 mutations (p = 0.55). CONCLUSION: OPA1-related ADOA generally progresses slowly and functional visual acuity is usually maintained. Longitudinal disease studies are important to enable appropriate counselling of patients. This study enables a better understanding of the natural history of ADOA.