Swiss Fleckvieh was established in 1970 as a composite of Simmental (SI) and Red Holstein Friesian (RHF) cattle. Breed composition is currently reported based on pedigree information. Information on a large number of molecular markers potentially provides more accurate information. For the analysis, we used Illumina BovineSNP50 Genotyping Beadchip data for 90 pure SI, 100 pure RHF and 305 admixed bulls. The scope of the study was to compare the performance of hidden Markov models, as implemented in structure software, with methods conventionally used in genomic selection [BayesB, partial least squares regression (PLSR), least absolute shrinkage and selection operator (LASSO) variable selection)] for predicting breed composition. We checked the performance of algorithms for a set of 40 492 single nucleotide polymorphisms (SNPs), subsets of evenly distributed SNPs and subsets with different allele frequencies in the pure populations, using F(ST) as an indicator. Key results are correlations of admixture levels estimated with the various algorithms with admixture based on pedigree information. For the full set, PLSR, BayesB and structure performed in a very similar manner (correlations of 0.97), whereas the correlation of LASSO and pedigree admixture was lower (0.93). With decreasing number of SNPs, correlations decreased substantially only for 5% or 1% of all SNPs. With SNPs chosen according to F(ST) , results were similar to results obtained with the full set. Only when using 96 and 48 SNPs with the highest F(ST) , correlations dropped to 0.92 and 0.90 respectively. Reducing the number of pure animals in training sets to 50, 20 and 10 each did not cause a drop in the correlation with pedigree admixture.

The triple-helical domain of type VII collagen was isolated from human placental membranes by mild digestion with pepsin, and polyclonal antibodies were raised in rabbits against this protein. After affinity purification the antibodies specifically recognized type VII collagen in both the triple-helical and the unfolded state. They also reacted with the fragments P1 and P2, derived from the triple-helical domain by further proteolysis with pepsin, but did not crossreact with other biochemical components of the dermal connective tissue.In skin the presence of a fragment of type VII collagen, similar to that isolated from placenta, was demonstrated by SDS-PAGE and immunoblotting. Type VII collagen represented less than 0.001% of the total collagen extracted by pepsin digestion from newborn or adult skin.The tissue form of type VII collagen was obtained from dermis after artificial epidermolysis with strongly denaturing buffers under conditions reducing disulfide bonds. The protein was identified by immunoblotting with the antibodies. The molecule was composed of three polypeptides with an apparent molecular mass of about 250 kDa, each. Similar large-molecular-mass chains could be identified by immunoblotting in extracts of human fibroblasts in culture.Anchoring fibrils are well-known suprastructures of skin. They presumably mediate the attachment of the epidermis to the underlying dermal connective tissue [l -31. At their upper end they are inserted into the basement membrane zone of the dermo-epidermal junction. Their lower end can be localized among the connective tissue fibers in the most superficial layer of dermis, i.e. the papillary dermis. The lateral density of anchoring fibrils varies significantly from one location to another in normal skin [2]; and in some genetic disorders, such as hereditary epidermolysis bullosa, the fibrils appear to be defective or absent [4 -61. There are various collagenous suprastructures in skin containing the interstitial collagens type I, 111, V and VI. The dermo-epidermal basement membrane consists in part of typeIV collagen [7, 81. Anchoring fibrils are also of collagenous nature. Sakai and coworkers recently demonstrated by immunoelectron microscopy that type VII is an important structural component of these fibrils [9].Type VII collagen was first isolated as peptic fragments from human fetal membranes. It contains a triple-helical domain 1.5 times the length of the interstitial collagens and, therefore, was first called long-chain collagen [lo]. It comprises three supposedly identical disulfide-linked chains and can be fragmented by pepsin to yield the characteristic polypeptides P1 and P2.

Recessive dystrophic epidermolysis bullosa with junctional blisters includes both the classical epidermolysis bullosa hereditaria letalis Herlitz (Herlitz-Pearson type) and a recently separated more benign adult type. Ultrastructural examination was performed of 13 skin specimens from 3 cases of the Herlitz-Pearson-type and one case of the adult type. Principal ultrastructural changes in involved, intact and experimentally frictioned skin regions, common to all patients, are as follows: In nonseparated areas hypoplasia of the hemi-desmosomes and mild decrease of the tonofibrils are found. Hypoplasia of hemi-desmosomes consists of a marked rudimentary structure of the sub-basal dense plaque and the attachment plaque. Focal widening of the lamina lucida suggesting early blistering occurs exclusively in the areas devoid of hemidesmosomes. In separated areas cleavage always occurs in the plane of lamina lucida, viz. the mode of blistering is junctional. Fragments of basal cells are often encountered still remaining attached to the blister floor ("epidermolytic torn-off phenomenon"). These torn-off portions of basal cells are characterized by relatively rich distribution of hemidesmosomes. Basal cells forming the blister roof frequently show small gaps of basal plasma membrane and rarefaction of the basal part of the cytoplasm, which are thought to be secondary changes. Among the observed alterations, structural defects of hemidesmosomes are considered to play the most important role in the pathogenesis of junctional blisters.

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A 38-year-old patient with epidermolysis bullosa is described, in whom junctional blister formation is revealed by electron microscopy. Clinical and ultrastructural differences from the recessive dystrophic type (Hallopeau-Siemens) and from the lethal type (Herlitz) of epidermolysis bullosa are discussed in detail.

-Daily feed intake data of 1 279 French Landrace (FL, 1 039 boars and 240 castrates) and 2 417 Large White (LW, 2 032 boars and 385 castrates) growing pigs were recorded with electronic feed dispensers in three French central testing stations from 1992-1994. Male (35 to 95 kg live body weight) or castrated (100 kg live body weight) group housed, ad libitum fed pigs were performance tested. A quadratic polynomial in days on test with fixed regressions for sex and batch, random regressions for additive genetic, pen, litter and individual permanent environmental effects was used, with two different models for the residual variance: constant in model 1 and modelled with a quadratic polynomial depending on the day on test d m as follows in model 2:Variance components were estimated from weekly means of daily feed intake by means of a Bayesian analysis using Gibbs sampling. Posterior means of (co)variances were calculated using 800 000 samples from four chains (200 000 each). Heritability estimates of regression coefficients were 0.30 (FL model 1), 0.21 (FL model 2), 0.14 (LW1) and 0.14 (LW2) for the intercept, 0.04 (FL1), 0.04 (FL2), 0.11 (LW1) and 0.06 (LW2) for the linear, 0.03 (FL1), 0.04 (FL2) 0.11 (LW1) and 0.06 (LW2) for the quadratic term. Heritability estimates for weekly means of daily feed intake were the lowest in week 4 (FL1: 0.11, FL2: 0.11) and week 1 (LW1: 0.09, LW2: 0.10), and the highest in week 11 (FL1: 0.25, FL2: 0.24) and week 8 (LW1: 0.19, LW2: 0.18), respectively. Genetic eigenfunctions revealed that altering the shape of the feed intake curve by selection is difficult. random regression / variance component / Gibbs sampling / feed intake / pig * Correspondence and reprints Present address: Swiss Brown Cattle Breeders' Federation,

To determine the prevalence of congenital melanonevocytic nevi (CMN), of so-called congenital nevus-like nevi (CNLN), nevi spili (NS) and café-au-lait spots (CLS) in childhood, a series of 939 children aged 8–16 years had total skin examination. CMN/CNLN were observed in a frequency of 5.9% NS in 2.1 % and CLS even in 32.7%. Except CLS (which occurred more frequently in boys) all of these lesions were equally represented in both sexes. According to the classification of Kopf and coworkers, 44/55 CMN/CNLN were small and 11/55 medium-sized. CMN/CNLN affected preferentially trunk and upper limbs while head and neck were spared. Such nevi occurred more frequently in dark types of skin complexion and showed a tendency to be more frequent in groups of patients with increased average number of acquired melanonevocytic nevi. Remarkably, CLS were also found in 23/55 (41.7%) children with CMN/CNLN and in 12/20 (60%) children with NS (in a higher frequency than such combinations have to be expected). Compared with the data from other studies both CMN/CNLN and CLS in our patients were observed in highest prevalence in the literature. Since the frequency of CLS in adults is much lower, it cannot be ruled out that some of the CLS disappear in adolescence.

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