Correction to: Unexpected high frequency of neurofibroma in the celiac ganglion of German cattle.

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Unexpected high frequency of neurofibroma in the celiac ganglion of German cattle.

In a study originally designed to find potential risk factors for bovine spongiform encephalopathy (BSE) we examined tissues from 403 Holstein Frisian cattle in total. These included 20 BSE cattle and their 236 birth- and feeding cohort animals plus 32 offspring, 103 age, breed and district-matched control cattle and further twelve cattle with neurological signs. In addition to the obex, we examined the celiac ganglion, cervical cranial ganglion, trigeminal ganglion and proximal ganglion of the vagus nerve using histological techniques. Unexpectedly, we found a high number of neurofibroma, a benign peripheral nerve sheath tumor consisting of Schwann cells, fibroblasts and perineural cells. The neurofibroma were present only in the celiac ganglion and found during histologic examination. With a frequency of 9.91% in BSE cattle and their cohorts (case animals) and 9.09% in the age, breed and district matched control animals there seems to be no correlation between the occurrence of BSE and neurofibroma. Benign peripheral nerve sheath tumors have been described more often in cattle than in other domestic animals. Usually, they are incidental macroscopic findings in the thoracic ganglia during meat inspection. To our knowledge, there are no previous systematic histologic studies including bovine celiac ganglia at all. The high incidence of celiac ganglia neurofibroma may play a role in the frequently occurring abomasal displacements in Holstein Frisian cattle as the tumors might cause a gastrointestinal motility disorder. At present a genetic predisposition for these neoplasms cannot be ruled out.

A genome-wide association study reveals a locus for bilateral iridal hypopigmentation in Holstein Friesian cattle.

BACKGROUND: Eye pigmentation abnormalities in cattle are often related to albinism, Chediak-Higashi or Tietz like syndrome. However, mutations only affecting pigmentation of coat color and eye have also been described. Herein 18 Holstein Friesian cattle affected by bicolored and hypopigmented irises have been investigated. RESULTS: Affected animals did not reveal any ophthalmological or neurological abnormalities besides the specific iris color differences. Coat color of affected cattle did not differ from controls. Histological examination revealed a reduction of melanin pigment in the iridal anterior border layer and stroma in cases as cause of iris hypopigmentation. To analyze the genetics of the iris pigmentation differences, a genome-wide association study was performed using Illumina BovineSNP50 BeadChip genotypes of the 18 cases and 172 randomly chosen control animals. A significant association on bovine chromosome 8 (BTA8) was identified at position 60,990,733 with a -log10(p) = 9.17. Analysis of genotypic and allelic dependences between cases of iridal hypopigmentation and an additional set of 316 randomly selected Holstein Friesian cattle controls showed that allele A at position 60,990,733 on BTA8 (P = 4.0e-08, odds ratio = 6.3, 95% confidence interval 3.02-13.17) significantly increased the chance of iridal hypopigmentation. CONCLUSIONS: The clinical appearance of the iridal hypopigmentation differed from previously reported cases of pigmentation abnormalities in syndromes like Chediak-Higashi or Tietz and seems to be mainly of cosmetic character. Iridal hypopigmentation is caused by a reduced content of melanin pigment in the anterior border layer and iridal stroma. A single genomic position on BTA8 was detected to be significantly associated with iridal hypopigmentation in examined cattle. To our knowledge this is the first report about this phenotype in Holstein Friesian cattle.

PrPSc spreading patterns in the brain of sheep linked to different prion types.

Scrapie in sheep and goats has been known for more than 250 years and belongs nowadays to the so-called prion diseases that also include e.g. bovine spongiform encephalopathy in cattle (BSE) and Creutzfeldt-Jakob disease in humans. According to the prion hypothesis, the pathological isoform (PrPSc) of the cellular prion protein (PrPc) comprises the essential, if not exclusive, component of the transmissible agent. Currently, two types of scrapie disease are known--classical and atypical/Nor98 scrapie. In the present study we examine 24 cases of classical and 25 cases of atypical/Nor98 scrapie with the sensitive PET blot method and validate the results with conventional immunohistochemistry. The sequential detection of PrPSc aggregates in the CNS of classical scrapie sheep implies that after neuroinvasion a spread from spinal cord and obex to the cerebellum, diencephalon and frontal cortex via the rostral brainstem takes place. We categorize the spread of PrPSc into four stages: the CNS entry stage, the brainstem stage, the cruciate sulcus stage and finally the basal ganglia stage. Such a sequential development of PrPSc was not detectable upon analysis of the present atypical/Nor98 scrapie cases. PrPSc distribution in one case of atypical/Nor98 scrapie in a presumably early disease phase suggests that the spread of PrPSc aggregates starts in the di- or telencephalon. In addition to the spontaneous generation of PrPSc, an uptake of the infectious agent into the brain, that bypasses the brainstem and starts its accumulation in the thalamus, needs to be taken into consideration for atypical/Nor98 scrapie.

Similarities between forms of sheep scrapie and Creutzfeldt-Jakob disease are encoded by distinct prion types.

Transmissible spongiform encephalopathies such as scrapie in sheep, Creutzfeldt-Jakob disease (CJD) in humans, and bovine sporadic encephalopathy in cattle are characterized by the accumulation of a misfolded protein: the pathological prion protein. Ever since bovine sporadic encephalopathy was discovered as the likely cause of the new variant of CJD in humans, parallels between human and animal transmissible spongiform encephalopathies must be viewed under the aspect of a disease risk for humans. In our study we have compared prion characteristics of different forms of sheep scrapie with those of different phenotypes of sporadic CJD. The disease characteristics of sporadic CJD depend considerably on the prion type 1 or 2. Our results show that there are obvious parallels between sporadic CJD type 1 and the so-called atypical/Nor98 scrapie. These parelleles apply to the deposition form of pathological prion protein in the brain, detected by the paraffin-embedded-tissue blot and the prion aggregate stability with regard to denaturation by the chaotropic salt guanidine hydrochloride. The same applies to sporadic CJD type 2 and classical scrapie. The observed parallels between types of sporadic CJD and types of sheep scrapie demonstrate that distinct groups of prion disease exist in different species. This should be taken into consideration when discussing interspecies transmission.

Morgagnian cataract resulting from a naturally occurring nonsense mutation elucidates a role of CPAMD8 in mammalian lens development.

To investigate the genetic basis of hereditary lens opacities we analyzed 31 cases of bilateral congenital cataract in Red Holstein Friesian cattle. A genome-wide association study revealed a significant association on bovine chromosome 7 at positions 6,166,179 and 12,429,691. Whole genome re-sequencing of one case and four relatives showed a nonsense mutation (g.5995966C>T) in the PZP-like, alpha-2-macroglobulin domain containing 8 (CPAMD8) gene leading to a premature stop codon (CPAMD8 p.Gln74*) associated with cataract development in cattle. With immunohistochemistry we confirmed a physiological expression of CPAMD8 in the ciliary body epithelium of the eye in unaffected cattle, while the protein was not detectable in the ciliary body of cattle with cataracts. RNA expression of CPAMD8 was detected in healthy adult, fetal and cataractous lenses.

The Holstein Friesian Lethal Haplotype 5 (HH5) Results from a Complete Deletion of TBF1M and Cholesterol Deficiency (CDH) from an ERV-(LTR) Insertion into the Coding Region of APOB.

BACKGROUND: With the availability of massive SNP data for several economically important cattle breeds, haplotype tests have been performed to identify unknown recessive disorders. A number of so-called lethal haplotypes, have been uncovered in Holstein Friesian cattle and, for at least seven of these, the causative mutations have been identified in candidate genes. However, several lethal haplotypes still remain elusive. Here we report the molecular genetic causes of lethal haplotype 5 (HH5) and cholesterol deficiency (CDH). A targeted enrichment for the known genomic regions, followed by massive parallel sequencing was used to interrogate for causative mutations in a case/control approach. METHODS: Targeted enrichment for the known genomic regions, followed by massive parallel sequencing was used in a case/control approach. PCRs for the causing mutations were developed and compared to routine imputing in 2,100 (HH5) and 3,100 (CDH) cattle. RESULTS: HH5 is caused by a deletion of 138kbp, spanning position 93,233kb to 93,371kb on chromosome 9 (BTA9), harboring only dimethyl-adenosine transferase 1 (TFB1M). The deletion breakpoints are flanked by bovine long interspersed nuclear elements Bov-B (upstream) and L1ME3 (downstream), suggesting a homologous recombination/deletion event. TFB1M di-methylates adenine residues in the hairpin loop at the 3'-end of mitochondrial 12S rRNA, being essential for synthesis and function of the small ribosomal subunit of mitochondria. Homozygous TFB1M-/- mice reportedly exhibit embryonal lethality with developmental defects. A 2.8% allelic frequency was determined for the German HF population. CDH results from a 1.3kbp insertion of an endogenous retrovirus (ERV2-1-LTR_BT) into exon 5 of the APOB gene at BTA11:77,959kb. The insertion is flanked by 6bp target site duplications as described for insertions mediated by retroviral integrases. A premature stop codon in the open reading frame of APOB is generated, resulting in a truncation of the protein to a length of only <140 amino acids. Such early truncations have been shown to cause an inability of chylomicron excretion from intestinal cells, resulting in malabsorption of cholesterol. The allelic frequency of this mutation in the German HF population was 6.7%, which is substantially higher than reported so far. Compared to PCR assays inferring the genetic variants directly, the routine imputing used so far showed a diagnostic sensitivity of as low as 91% (HH5) and 88% (CDH), with a high specificity for both (≥99.7%). CONCLUSION: With the availability of direct genetic tests it will now be possible to more effectively reduce the carrier frequency and ultimately eliminate the disorders from the HF populations. Beside this, the fact that repetitive genomic elements (RE) are involved in both diseases, underline the evolutionary importance of RE, which can be detrimental as here, but also advantageous over generations.

Correction: The Holstein Friesian Lethal Haplotype 5 (HH5) Results from a Complete Deletion of TBF1M and Cholesterol Deficiency (CDH) from an ERV-(LTR) Insertion into the Coding Region of APOB.

[This corrects the article DOI: 10.1371/journal.pone.0154602.].