Genome sequence, comparative analysis, and population genetics of the domestic horse

We report a high-quality draft sequence of the genome of the horse (Equus caballus). The genome is relatively repetitive but has little segmental duplication. Chromosomes appear to have undergone few historical rearrangements: 53% of equine chromosomes show conserved synteny to a single human chromosome. Equine chromosome 11 is shown to have an evolutionary new centromere devoid of centromeric satellite DNA, suggesting that centromeric function may arise before satellite repeat accumulation. Linkage disequilibrium, showing the influences of early domestication of large herds of female horses, is intermediate in length between dog and human, and there is long-range haplotype sharing among breeds.

Normal variability of static perimetric threshold values across the central visual field

We assessed the variability of results in normal subjects of computerized static threshold perimetry of the central 30 degrees field. Variability of measured threshold values was highly dependent on eccentricity. This included variability among individuals, test-to-test variability within individuals, and intratest variability. All values were significantly larger in the midperiphery than centrally. We found that the mean sensitivity decrement with age was eccentricity dependent, so that the age-corrected normal visual field became not only depressed but also steeper with age. Distributions of individual pointwise deviations from the age-corrected normal mean thresholds were significantly nongaussian. The dependency of variability on test point location, the nongaussian distributions of deviations from age-corrected means, and the variability of age-induced sensitivity reduction should all be considered in the interpretation of computerized visual fields, and particularly in the design of statistical programs for field analysis. Programs not considering these factors are likely to result in misleading analyses.

Test-retest variability in glaucomatous visual fields

We measured test-retest variations in computerized visual fields from glaucomatous eyes. Fifty-one patients were tested four times within a four-week period; the severity of disease varied from incipient to advanced. We determined the dependence of threshold variability on defect depth and test point location. In areas of the visual field initially found to have moderate loss of sensitivity, variation in follow-up measurements ranged from normal sensitivity to absolute defect, with little dependence on distance from fixation. Conversely, large changes were considerably more unusual in locations initially showing normal or near-normal sensitivities, and variability was lowest in the most central portion of the field. Our findings suggest that differentiation between true progression and random variation will be facilitated if these factors are taken into account, as well as if comparisons are based on more than two tests. The complex nature of interest variation in glaucoma makes it natural to approach this problem with the help of computer-assisted analyses.

The effect of perimetric experience in normal subjects

Two groups of normal subjects were submitted to repeated automated static threshold perimetry. Perimetric results were strongly affected by the level of experience in some subjects; in the majority, however, the effect of experience was small. Initial field tests often showed high numbers of depressed points. Sensitivity increased with perimetric training, particularly between the first sessions. Those subjects who improved most started low, gradually approaching normal levels with experience. Learning effects were more pronounced peripherally than paracentrally and "untrained" fields characteristically showed concentric contraction with numerous points with low sensitivity peripherally. An important practical conclusion is to allow repeated testing of all inexperienced patients in whom initial fields do not agree with clinical findings. A chart showing a concentrically narrowed field should be viewed with particular suspicion. Furthermore, a single initial field may constitute an inadequate baseline for clinical follow-up.

Safety and efficacy of the mRNA BNT162b2 vaccine against SARS-CoV-2 in five groups of immunocompromised patients and healthy controls in a prospective open-label clinical trial

Background

Patients with immunocompromised disorders have mainly been excluded from clinical trials of vaccination against COVID-19. Thus, the aim of this prospective clinical trial was to investigate safety and efficacy of BNT162b2 mRNA vaccination in five selected groups of immunocompromised patients and healthy controls.

Methods

539 study subjects (449 patients and 90 controls) were included. The patients had either primary (n=90), or secondary immunodeficiency disorders due to human immunodeficiency virus infection (n=90), allogeneic hematopoietic stem cell transplantation/CAR T cell therapy (n=90), solid organ transplantation (SOT) (n=89), or chronic lymphocytic leukemia (CLL) (n=90). The primary endpoint was seroconversion rate two weeks after the second dose. The secondary endpoints were safety and documented SARS-CoV-2 infection.

Findings

Adverse events were generally mild, but one case of fatal suspected unexpected serious adverse reaction occurred. 72.2% of the immunocompromised patients seroconverted compared to 100% of the controls (p=0.004). Lowest seroconversion rates were found in the SOT (43.4%) and CLL (63.3%) patient groups with observed negative impact of treatment with mycophenolate mofetil and ibrutinib, respectively.

Interpretation

The results showed that the mRNA BNT162b2 vaccine was safe in immunocompromised patients. Rate of seroconversion was substantially lower than in healthy controls, with a wide range of rates and antibody titres among predefined patient groups and subgroups. This clinical trial highlights the need for additional vaccine doses in certain immunocompromised patient groups to improve immunity.

Funding

Knut and Alice Wallenberg Foundation, the Swedish Research Council, Nordstjernan AB, Region Stockholm, Karolinska Institutet, and organizations for PID/CLL-patients in Sweden.

Vaccine priming is restricted to draining lymph nodes and controlled by adjuvant-mediated antigen uptake

The innate immune mechanisms by which adjuvants enhance the potency and protection of vaccine-induced adaptive immunity are largely unknown. We introduce a model to delineate the steps of how adjuvant-driven innate immune activation leads to priming of vaccine responses using rhesus macaques. Fluorescently labeled HIV-1 envelope glycoprotein (Env) was administered together with the conventional aluminum salt (alum) adjuvant. This was compared to Env given with alum with preabsorbed Toll-like receptor 7 (TLR7) ligand (alum-TLR7) or the emulsion MF59 because they show superiority over alum for qualitatively and quantitatively improved vaccine responses. All adjuvants induced rapid and robust immune cell infiltration to the injection site in the muscle. This resulted in substantial uptake of Env by neutrophils, monocytes, and myeloid and plasmacytoid dendritic cells (DCs) and migration exclusively to the vaccine-draining lymph nodes (LNs). Although less proficient than monocytes and DCs, neutrophils were capable of presenting Env to memory CD4⁺ T cells. MF59 and alum-TLR7 showed more pronounced cell activation and overall higher numbers of Env⁺ cells compared to alum. This resulted in priming of higher numbers of Env-specific CD4⁺ T cells in the vaccine-draining LNs, which directly correlated with increased T follicular helper cell differentiation and germinal center formation. Thus, strong innate immune activation promoting efficient vaccine antigen delivery to infiltrating antigen-presenting cells in draining LNs is an important mechanism by which superior adjuvants enhance vaccine responses.

Fitness loss and germline mutations in barn swallows breeding in Chernobyl

The severe nuclear accident at Chernobyl in 1986 resulted in the worst reported accidental exposure of radioactive material to free-living organisms. Short-term effects on human populations inhabiting polluted areas include increased incidence of thyroid cancer, infant leukaemia, and congenital malformations in newborns. Two recent studies have reported, although with some controversy, that germline mutation rates were increased in humans and voles living close to Chernobyl, but little is known about the viability of the organisms affected. Here we report an increased frequency of partial albinism, a morphological aberration associated with a loss of fitness, among barn swallows, Hirundo rustica, breeding close to Chernobyl. Heritability estimates indicate that mutations causing albinism were at least partly of germline origin. Furthermore, evidence for an increased germline mutation rate was obtained from segregation analysis at two hypervariable microsatellite loci, indicating that mutation events in barn swallows from Chernobyl were two- to tenfold higher than in birds from control areas in Ukraine and Italy.

Height, weight and menarche in Swedish urban school children in relation to socio-economic and regional factors

During the period 1964-1973, a defined sample of 740 Swedish urban school children (360 girls and 380 boys) from 40 different urban areas all over the country were followed longitudinally. Height and weight were measured twice a year and age at menarche was recorded. Mean ages at peak height velocity (PHV) and peak weight velocity (PWV) were 11-91 years (SD 0-95) and 12-50 years (SD 1-08) for girls with average values of 8-30 cm/year (SD 1-32) and 7-37 kg/year (SD 1-94). Mean age at menarche was 13-05 years (SD 1-03). PHV and PWV in boys occurred on average at 14-09 years (SD 1-11) and 14-30 years (SD 1-11) with magnitudes of 9-84 cm/year (SD 1-40) and 9-07 kg/year (SD 2-04). No significant differences between socio-economic strata defined by father's occupation and family income were found either for height and weight or for ages at PHV, PWV and menarche. Girls but not boys in the lowest social group (III) had more weight for height during puberty than had girls in social groups I and II. Between the three main geographical regions of Sweden some differences were found. Boys in the South were at the ages of 17 and 18 on average heavier than boys from the rest of the country. Boys and girls in the South had PHV, PWV and menarche half a year later than children in Middle Sweden. In analysis of variance for age at PHV significant interaction terms were found for regions times urbanization. In the South and North age at PHV was earlier the higher the urbanization level, but in Middle Sweden the reverse occurred.

Induction of Robust B Cell Responses after Influenza mRNA Vaccination Is Accompanied by Circulating Hemagglutinin-Specific ICOS+ PD-1+ CXCR3+ T Follicular Helper Cells

Modified mRNA vaccines have developed into an effective and well-tolerated vaccine platform that offers scalable and precise antigen production. Nevertheless, the immunological events leading to strong antibody responses elicited by mRNA vaccines are largely unknown. In this study, we demonstrate that protective levels of antibodies to hemagglutinin were induced after two immunizations of modified non-replicating mRNA encoding influenza H10 encapsulated in lipid nanoparticles (LNP) in non-human primates. While both intradermal (ID) and intramuscular (IM) administration induced protective titers, ID delivery generated this response more rapidly. Circulating H10-specific memory B cells expanded after each immunization, along with a transient appearance of plasmablasts. The memory B cell pool waned over time but remained detectable throughout the 25-week study. Following prime immunization, H10-specific plasma cells were found in the bone marrow and persisted over time. Germinal centers were formed in vaccine-draining lymph nodes along with an increase in circulating H10-specific ICOS+ PD-1+ CXCR3+ T follicular helper cells, a population shown to correlate with high avidity antibody responses after seasonal influenza vaccination in humans. Collectively, this study demonstrates that mRNA/LNP vaccines potently induce an immunological repertoire associated with the generation of high magnitude and quality antibodies.

Swedish population reference standards for height, weight and body mass index attained at 6 to 16 years (girls) or 19 years (boys)

Swedish population reference standards for height, weight and body mass index (BMI) attained at 6 to 16 years (girls) or 19 years (boys) are presented. Data were obtained from two independent nationwide samples of Swedish children; one (740 children) born in 1955, the other (2907 children) born in 1967. The weights of the children born in 1955 were adjusted to equal those born in 1967; heights did not differ. These reference standards refer therefore to Swedish children born at around 1970. The observations were fitted by the power transformation, or L, M, S method of Cole and Green. Weights and BMIs were thus normalized and valid SD scores for individuals obtained. Centile charts are given for clinical use. The means of the present, nationwide standards were 1-2 cm and 1-2 kg greater than those of the Solna-based standards currently in use.

Statistical evaluation of cell kinetic data from DNA flow cytometry (FCM) by the EM algorithm

Flow cytometric DNA measurements yield the amount of DNA for each of a large number of cells. A DNA histogram normally consists of a mixture of one or more constellations of G0/G1-, S-, G2/M-phase cells, together with internal standards, debris, background noise, and one or more populations of clumped cells. We have modelled typical DNA histograms as a mixed distribution with Gaussian densities for the G0/G1 and G2/M phases, an S-phase density, assumed to be uniform between the G0/G1 and G2/M peaks, observed with a Gaussian error, and with Gaussian densities for standards of chicken and trout red blood cells. The debris is modelled as a truncated exponential distribution, and we also have included a uniform background noise distribution over the whole observation interval. We have explored a new approach for maximum-likelihood analyses of complex DNA histograms by the application of the EM algorithm. This algorithm was used for four observed DNA histograms of varying complexity. Our results show that the algorithm works very well, and it converges to reasonable values for all parameters. In simulations from the estimated models, we have investigated bias, variance, and correlations of the estimates.

Scientific rigour in qualitative research--examples from a study of women's health in family practice

The increase in qualitative research in family medicine raises a demand for critical discussions about design, methods and conclusions. This article shows how scientific claims for truthful findings and neutrality can be assessed. Established concepts such as validity, reliability, objectivity and generalization cannot be used in qualitative research. Alternative criteria for scientific rigour, initially introduced by Lincoln and Guba, are presented: credibility, dependability, confirmability and transferability. These criteria have been applied to a research project, a qualitative study with in-depth interviews with female patients suffering from chronic pain in the locomotor system. The interview data were analysed on the basis of grounded theory. The proposed indicators for scientific rigour were shown to be useful when applied to the research project. Several examples are given. Difficulties in the use of the alternative criteria are also discussed.

Adenoma prevalence and cancer risk in familial non-polyposis colorectal cancer

BACKGROUND AND AIMS

Polypectomy in the colon has been shown to prevent colorectal cancer in both the general population and in familial colorectal cancer. Individuals with a family history of colorectal cancer have an increased risk of the disease. Over a period of 10 years, 304 subjects at risk were included in ongoing surveillance with regular colonoscopies. To compile the medical findings and experience generated during this period, a retrospective cross sectional study was performed.

SUBJECTS

Subjects were classified into three family groups: families with hereditary non-polyposis colorectal cancer (HNPCC); families with hereditary colorectal cancer (HCC, non-Lynch syndrome); and a third group of families with only empirical risk estimates based on a family history of two close relatives (TCR) with colorectal cancer.

METHODS

The risk population was studied with regard to age at onset, prevalence, number, cancer risk, size, dysplasia, and distribution of adenomas. A comparison was made within the family groups and with a reference group representing the general population.

RESULTS

In total, 195 adenomas and six cancers were detected among 85 individuals. The relative risk of having an adenoma in the whole risk population compared with the general population was 2.6. Subjects from TCR families had most adenomas and HNPCC subjects had the least. A shift from proximal adenomas to distal carcinomas in families with HCC and TCR suggested a higher cancer risk in distal adenomas in these syndromes. HNPCC families showed a younger age at onset and adenomas with a higher degree of dysplasia. In HNPCC, there was a similar localisation of adenomas and carcinomas, suggesting a high risk of cancer in all adenomas.

CONCLUSIONS

There was clear overrepresentation of adenomas in all three family types compared with the reference population. In HNPCC, we found earlier onset of adenomas and faster progression to cancer. Families with HCC, and even more so TCR subjects, had a later onset and lower risk of cancer from proximal adenomas. Based on these results, surveillance protocols in Sweden have been revised.

Growth of schoolchildren with early, average and late ages of peak height velocity

A sample of Swedish urban schoolchildren (357 girls, 373 boys) born in 1954/55 followed from 10 to 18 years were grouped according to peak height velocity age (PHV age) into early, average and late maturers. Mean heights differed between the maturity groups at ages from 10.0 to 14.0 years for girls and 10.5 to 17.0 years for boys. Mean weights differed between the maturity groups at all ages up to 16.0 years for girls and up to 18.0 years for boys. The earlier the maturity process, the heavier for given height. The time differences between peak weight velocity (PWV) and PHV significantly differed between early, average and late maturers amounting to 0.9, 0.5 and 0.2 years respectively for girls and 0.6, 0.3 and -0.1 years respectively for boys. The time difference between menarche and PWV did not differ between the maturity groups and amounted to about 0.6 +/- 0.05 years (SD = 0.9). For boys a similar lack of difference between maturity groups was obtained concerning the time difference between secondary sex characteristics; stage 4 (SSC IV) and PWV. Mean height and weight for girls and boys differed between the maturity groups at PHV but not at PWV, menarche or SCC IV.

Visual field interpretation with empiric probability maps

Automated visual field charts may be difficult to interpret partly because of the magnitude and complex nature of normal threshold variability. We devised two types of empiric probability maps in which this variability is taken into account and the significances of measured threshold values are displayed. These maps are highly sensitive to nonobvious but significant paracentral field loss but will at the same time deemphasize false-positive patterns commonly found more peripherally. They also frequently show field defects before these are obvious in conventional threshold printouts. In addition, they differentiate between generalized loss of sensitivity and localized field defects.

The meanings of pain: an exploration of women's descriptions of symptoms

A grounded theory study with repeated semi-structured interviews was conducted to explore the meaning of the illness experiences of women patients, impaired by biomedically undefined musculoskeletal pain. Twenty female patients were recruited at an urban primary health care centre in northern Sweden, where two of the researchers work as family physicians. In this paper we focus on considerations of patient pain and analyze the findings from aspects linking together body, gender, and society. Four categories of symptom description were identified: bodily presentations, explanatory models, consequences of pain for the patient's activities, and consequences for her self-perception. The bodily symptoms signaled loss of control. The explanatory models consisted of physical damage and strain injuries, but were also psychological and self-blaming. The consequences of pain were described as negative consequences for the women's everyday life that challenged their self-perception as women. The participants' search and need for legitimization of their illness experiences, and the expectations placed on doctors as legitimizing agents was evident. To achieve the desired shared understanding in consultations, doctors must be aware of and consider not only physical signs and symptoms, but also the patients' gendered concerns and psycho-social circumstances.

"I've been crying my way"--qualitative analysis of a group of female patients' consultation experiences

BACKGROUND AND OBJECTIVES

What do women patients, sick-listed for biomedically undefined musculoskeletal disorders, expect and experience when they consult a doctor? With the purpose to learn more about this, a qualitative interview study was conducted.

METHODS

Twenty women participated. They were patients at an urban health care centre in northern Sweden. Data were gained through repeated, semi-structured interviews, and analysed according to grounded theory.

RESULTS

The participants described an atmosphere of distrust in the consultation. They had felt ignored, disregarded and rejected by doctors, and had worked out strategies to keep up medical attention in their search for a creditable diagnosis. They were somatizing, claiming under cover, and pleading, to catch the doctor's interest. In addition, they upheld their self-respect by mystifying and martyrizing themselves and their symptoms, and by condemning physicians as ignorant.

DISCUSSION

The patient's consultation experiences are discussed from different aspects; the biomedical framework, the power asymmetry, and the gendered positions of patient and doctor. The findings indicate the importance of making doctors aware of the context behind frustrations in doctor-patient interaction.

Particulate Array of Well-Ordered HIV Clade C Env Trimers Elicits Neutralizing Antibodies that Display a Unique V2 Cap Approach

The development of soluble envelope glycoprotein (Env) mimetics displaying ordered trimeric symmetry has ushered in a new era in HIV-1 vaccination. The recently reported native, flexibly linked (NFL) design allows the generation of native-like trimers from clinical isolates at high yields and homogeneity. As the majority of infections world-wide are of the clade C subtype, we examined responses in non-human primates to well-ordered subtype C 16055 trimers administered in soluble or high-density liposomal formats. We detected superior germinal center formation and enhanced autologous neutralizing antibodies against the neutralization-resistant (tier 2) 16055 virus following inoculation of liposome-arrayed trimers. Epitope mapping of the neutralizing monoclonal antibodies (mAbs) indicated major contacts with the V2 apex, and 3D electron microscopy reconstructions of Fab-trimer complexes revealed a horizontal binding angle to the Env spike. These vaccine-elicited mAbs target the V2 cap, demonstrating a means to accomplish tier 2 virus neutralization by penetrating the dense N-glycan shield.

Worldwide frequency distribution of the 'Gait keeper' mutation in the DMRT3 gene

For centuries, domestic horses have represented an important means of transport and served as working and companion animals. Although their role in transportation is less important today, many horse breeds are still subject to intense selection based on their pattern of locomotion. A striking example of such a selected trait is the ability of a horse to perform additional gaits other than the common walk, trot and gallop. Those could be four-beat ambling gaits, which are particularly smooth and comfortable for the rider, or pace, used mainly in racing. Gaited horse breeds occur around the globe, suggesting that gaitedness is an old trait, selected for in many breeds. A recent study discovered that a nonsense mutation in DMRT3 has a major impact on gaitedness in horses and is present at a high frequency in gaited breeds and in horses bred for harness racing. Here, we report a study of the worldwide distribution of this mutation. We genotyped 4396 horses representing 141 horse breeds for the DMRT3 stop mutation. More than half (2749) of these horses also were genotyped for a SNP situated 32 kb upstream of the DMRT3 nonsense mutation because these two SNPs are in very strong linkage disequilibrium. We show that the DMRT3 mutation is present in 68 of the 141 genotyped horse breeds at a frequency ranging from 1% to 100%. We also show that the mutation is not limited to a geographical area, but is found worldwide. The breeds with a high frequency of the stop mutation (>50%) are either classified as gaited or bred for harness racing.

Genetical and physical assignments of equine microsatellites--first integration of anchored markers in horse genome mapping

Twenty equine microsatellites were isolated from a genomic phage library, and their genetical and physical localization was sought by linkage mapping and fluorescent in situ hybridization (FISH). Nineteen of the markers were found to be polymorphic with, in most cases, heterozygosities exceeding 50%. The markers were mapped in a Swedish reference family for gene mapping, comprising eight half-sib families from Standardbred and Icelandic horse sires. Segregation was analyzed against a set of 35 other markers typed in the pedigree. Thirteen of the microsatellites showed linkage to at least one other marker, with a total of 21 markers being involved in these linkages. In parallel, 18 of the microsatellites could be assigned to their chromosomal region by FISH. These assignments involved eight equine autosomes: ECA1, 2, 4, 6, 9, 10, 15, and 16. The genetical and physical mappings revealed by this study represent a significant extension of the current knowledge of the equine genome map.

First comprehensive low-density horse linkage map based on two 3-generation, full-sibling, cross-bred horse reference families

Two 3-generation full-sibling reference families have been produced and form a unique resource for genetic linkage mapping studies in the horse. The F(2) generations, now comprising 61 individuals, consist of 28- to 32-day-old embryos removed nonsurgically from two pairs of identical twin mares. The same stallion sired all F(2)s such that the two full-sibling families are half-sibling with respect to each other. The families are crossbred to maximize levels of heterozygosity and include Arabian, Thoroughbred, Welsh Cob, and Icelandic Horse breeds. Milligram quantities of DNA have been isolated from each embryo and from blood samples of the parents and grandparents. The families have been genotyped with 353 equine microsatellites and 6 biallelic markers, and 42 linkage groups were formed. In addition, the physical location of 85 of the markers is known, and this has allowed 37 linkage groups to be anchored to the physical map. The inclusion of dams in the genotyping analysis has allowed the generation of a genetic map of the X chromosome. Markers have been assigned to all 31 autosomes and the X chromosome. The average interval between markers on the map is 10.5 cM, and the linkage groups collectively span 1780 cM. The results demonstrate the benefits for horse linkage mapping studies of genotyping on these unique full-sibling families, which comprise relatively few individuals, by the generation of a comprehensive low-density map of the horse genome.

Perimetric probability maps to separate change caused by glaucoma from that caused by cataract

We describe a new method for analysis of change in glaucomatous visual fields with the object to differentiate between changes caused by glaucoma from those caused by cataract. New pattern deviation change probability maps were developed from a prospectively collected glaucoma material and designed to be sensitive to changes in localized field loss, but to be unaffected by media-induced perimetric change. We compared the new change probability maps with the commercially available total deviation change probability maps in series of Humphrey perimetric tests in a glaucoma material of 43 eyes of 35 patients, who had undergone cataract surgery. When using the total deviation maps, considerable differences were seen between fields obtained before and after cataract surgery. Much smaller differences were seen when using the new change probability maps, that almost eliminated the common and disturbing effect of increasing cataract. This new tool could be of considerable help in differentiation between progressive glaucomatous visual field loss and deterioration caused by increasing media opacities.

Carboxyl-terminal prodomain-deleted human leukocyte elastase and cathepsin G are efficiently targeted to granules and enzymatically activated in the rat basophilic/mast cell line RBL

The hematopoietic neutral serine proteases leukocyte elastase and cathepsin G are synthesized as inactive precursors, but become activated by removal of an amino-terminal dipeptide and are stored in granules. Moreover, the pro forms of elastase and cathepsin G show carboxyl-terminal prodomains of 20 and 11 amino acids, respectively, which are not present in the mature enzymes. To investigate mechanisms of processing, activation, and granular targeting, we have utilized transgenic expression of myeloid serine proteases in the rat basophilic/mast cell line RBL-1 (Gullberg, U., Lindmark, A., Nilsson, E., Persson, A.-M., and Olsson, I. (1994) J. Biol. Chem. 269, 25219-25225). Leukocyte elastase was stably expressed in RBL-1 cells, and the translation products were characterized by biosynthetic labeling followed by immunoprecipitation, SDS-polyacrylamide gel electrophoresis, and fluorography. Processing of a main pro form of 34 kDa into mature 31- and 29-kDa forms was demonstrated. Translocation of mature forms to granule-containing fractions was shown by subcellular fractionation experiments. The processed forms were enzymatically active, judging by the occurrence of amino-terminal processing demonstrated by radiosequence analysis, the acquisition of affinity for the protease inhibitor aprotinin, and the appearance of elastase activity in transfected RBL cells. To investigate the function of the carboxyl-terminal prodomains, deletion mutants of leukocyte elastase and cathepsin G lacking the carboxyl-terminal extension were constructed and transfected into RBL cells. Our results show that as full-length proteins, the deletion mutants were converted to active enzymes and transferred to granules with kinetics similar to that of wild-type enzymes. We conclude that human leukocyte elastase and cathepsin G are converted into enzymatically active forms when expressed in RBL cells and targeted for storage in granules; the carboxyl-terminal prodomains are necessary neither for enzymatic activation nor for targeting to granules in RBL cells.

Report of the International Equine Gene Mapping Workshop: male linkage map

The goal of the First International Equine Gene Mapping Workshop, held in 1995, was the construction of a low density, male linkage map for the horse. For this purpose, the International Horse Reference Family Panel (IHRFP) was established, consisting of 12 paternal half-sib families with 448 half-sib offspring provided by 10 laboratories. Blood samples were collected and DNA extracted in each laboratory and sent to the Lexington laboratory (KY, USA) for dispatch in aliquots to 14 typing laboratories. In total, 161 markers (144 microsatellites, seven blood groups and 10 proteins) were tested for all families for which the sire was heterozygous. Genealogies and typing data were sent for analysis to the INRA laboratory (Jouy-en-Josas, France) according to a specific format and entered into a database with input verification and output processes. Linkage analysis was performed with the CRIMAP program. Significant linkage was detected for 124 loci, of which 95 were unambiguously ordered using a multipoint analysis with an average spacing of 14.2 CM. These loci were distributed among 29 linkage groups. A more comprehensive analysis including synteny group data and FISH data suggested that 26 autosomes out of 31 are covered. The complete map spans 936 CM.