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During the COVID-19 pandemic, changes in vessel activity and associated noise have been reported globally. Sarasota Bay is home to a large and increasing number of recreational vessels as well as a long-term resident community of bottlenose dolphins, Tursiops truncatus. Data were analyzed from two hydrophones to compare the soundscape during the COVID-19 pandemic to previous years (March–May 2020 and 2018/2019). Hourly metrics were calculated: vessel passes, 95th percentile sound levels [125 Hz and 16 kHz third octave bands (TOBs), and two broader bands: 88–1122 Hz and 1781–17 959 Hz], and dolphin whistle detection to understand changes in vessel activity and the effect on wildlife. Vessel activity increased during COVID-19 restrictions by almost 80% at one site and remained the same at the other site. Of the four sound level measures, only the 125 Hz TOB and 88–1122 Hz band increased with vessel activity at both sites, suggesting that these may be appropriate measures of noise from rapid pass-bys of small vessels in very shallow (

Supplementary Text; Figs. S1 to S8; Tables S1 to S5

Bottlenose dolphins managed under human care, human beings and Dalmatian dogs are prone to forming urate uroliths. Limiting dietary purine intake limits urate urolith formation in people and dogs because purines are metabolized to uric acid, which is excreted in urine. Managed dolphins develop ammonium urate nephroliths, whereas free-ranging dolphins do not. Free-ranging dolphins consume live fish, whereas managed dolphins consume different species that have been stored frozen and thawed. Differences in the purine content of fish consumed by dolphins under human care versus in the wild may be responsible for the difference in urolith prevalence. Commercially available purine assays measure only four purines, but reported changes in purines during frozen storage suggest that a wider range of metabolites should be measured when comparing fresh and stored fish. A method using high performance liquid chromatography with tandem mass spectrometry was developed to quantify eight purine metabolites in whole fish and squid commonly consumed by dolphins. The coefficient of variation within and among days was sometimes high for purines present in small amounts but was acceptable (≤ 25%) for guanine, hypoxanthine, and inosine, which were present in high concentrations. This expanded assay identified a total purine content up to 2.5 times greater than the total that would be quantified if only four purines were measured. Assuming additional purines are absorbed, these results suggest that additional purine metabolites should be measured to better understand the associated risk when fish or other purine-rich foods are consumed by people or animals prone to developing uroliths.

The CD45 antigen is essential for normal antigen receptor-mediated signalling in lymphocytes, and different patterns of splicing of CD45 are associated with distinct functions in lymphocytes. Abnormal CD45 splicing has been recognized in humans, caused by a C77G transversion in the gene encoding CD45 (PTPRC). Recently the C77G polymorphism has been associated with multiple sclerosis and increased susceptibility to HIV-1 infection. These studies suggest that the regulation of CD45 splicing may be critical for the proper function of the immune system. Because of these data we examined the frequency of the C77G allele in African and Asian populations from countries with high or low prevalence of HIV infection. Here we report that the variant CD45 C77G allele is absent in African populations. We further show that populations living in the Pamir mountains of Central Asia have a very high prevalence of the C77G variant.

Histological features of 12 biopsy specimens from patients with ichthyosis inherited as a dominant trait were compared with 15 specimens from patients with ichthyosis inherited as a sex-linked recessive trait and with 12 control sections from normal skin. Characteristic features that distinguished each inherited variety were described. The histology of sex-linked ichthyosis is very similar to that of non-bullous ichthyosiform erythrodermia.

Beta thalassemia is an autosomal recessive disorder characterized by reduced (beta(+)) or absent (beta(0)) beta-globin chain synthesis. In Lebanon it is the most predominant genetic defect. In this study we investigated the religious and geographic distribution of the beta-thalassemia mutations identified in Lebanon, and traced their precise origins. A total of 520 beta-globin chromosomes from patients of different religious and regional backgrounds was studied. Beta thalassemia mutations were identified using Amplification Refractory Mutation System (ARMS) PCR or direct gene sequencing. Six (IVS-I-110, IVS-I-1, IVS-I-6, IVS-II-1, cd 5 and the C > T substitution at cd 29) out of 20 beta-globin defects identified accounted for more than 86% of the total beta-thalassemia chromosomes. Sunni Muslims had the highest beta-thalassemia carrier rate and presented the greatest heterogeneity, with 16 different mutations. Shiite Muslims followed closely with 13 mutations, whereas Maronites represented 11.9% of all beta-thalassemic subjects and carried 7 different mutations. RFLP haplotype analysis showed that the observed genetic diversity originated from both new mutational events and gene flow from population migration. This study provides information about the types and distribution of beta-thalassemia mutations within each religious group and geographic region, which is essential for the implementation of screening and prevention programs.

We have developed a semi-automated HLA class I typing system utilising TET/TAMRA-labelled fluorescence resonance energy transfer (FRET) hydrolysis probes. The results from 87 individuals are in full concordance with serology and conventional gel-based systems. This assay replaces labour-intensive conventional gel-based DNA typing and has a higher allelic resolution than serology. Our approach differs from previously published fluorogenic probe typing protocols in that it provides simultaneous typing of HLA-A, -B and -C loci to medium resolution. Furthermore, by using equipment that is not specific to FRET probe analysis our system has in-built expansion capacity to 384 reactions per plate, thus making it applicable to high-throughput population screening. Automation is achieved through the use of computer software which analyses direct input from the fluorescence reader, allowing high throughput with a low inherent error rate.

Little is known regarding the rates at which natural selection can modify or retain antigen presenting alleles at the major histocompatibility complex (MHC). Discovery of identical [1101 base pairs (bp)] coding regions at the MHC class I C locus in Pan troglodytes and Pan paniscus, chimpanzee species that diverged approximately 2.3 million years ago, now indicates that a class I allotype can survive for at least this period. Remarkable conservation was also reflected in the (1799 bp) introns where a maximum of only six substitutions distinguished five alleles (three from P. troglodytes and two from P. paniscus) that encoded the identical heavy chain allotype. Analysis of a more distantly related human allele, HLA-Cw*0702, corroborated that intron variation was non-uniform along the gene. Thus we provide a clear reference frame for the lifetime of an MHC class I allotype, a direct estimate of allelic substitution rates, and evidence for an unusual evolution of MHC class I introns.

The nonrecombining portion of the human Y chromosome has proven to be a valuable tool for the study of population history. The maintenance of extended haplotypes characteristic of particular geographic regions, despite extensive admixture, allows complex demographic events to be deconstructed. In this study we report the frequencies of 23 Y-chromosome biallelic polymorphism haplotypes in 1,935 men from 49 Eurasian populations, with a particular focus on Central Asia. These haplotypes reveal traces of historical migrations, and provide an insight into the earliest patterns of settlement of anatomically modern humans on the Eurasian continent. Central Asia is revealed to be an important reservoir of genetic diversity, and the source of at least three major waves of migration leading into Europe, the Americas, and India. The genetic results are interpreted in the context of Eurasian linguistic patterns.

We have developed a semi-automated HLA class I typing system utilising TET/TAMRA-labelled fluorescence resonance energy transfer (FRET) hydrolysis probes. The results from 87 individuals are in full concordance with serology and conventional gel-based systems. This assay replaces labour-intensive conventional gel-based DNA typing and has a higher allelic resolution than serology. Our approach differs from previously published fluorogenic probe typing protocols in that it provides simultaneous typing of HLA-A, -B and -C loci to medium resolution. Furthermore, by using equipment that is not specific to FRET probe analysis our system has in-built expansion capacity to 384 reactions per plate, thus making it applicable to high-throughput population screening. Automation is achieved through the use of computer software which analyses direct input from the fluorescence reader, allowing high throughput with a low inherent error rate.

Binary polymorphisms associated with the non-recombining region of the human Y chromosome (NRY) preserve the paternal genetic legacy of our species that has persisted to the present, permitting inference of human evolution, population affinity and demographic history 1 . We used denaturing highperformance liquid chromatography (DHPLC; ref. 2) to identify 160 of the 166 bi-allelic and 1 tri-allelic site that formed a parsimonious genealogy of 116 haplotypes, several of which display distinct population affinities based on the analysis of 1062 globally representative individuals. A minority of contemporary East Africans and Khoisan represent the descendants of the most ancestral patrilineages of anatomically modern humans that left Africa between 35,000 and 89,000 years ago.

HLA-A*2402 is common and widely distributed in human populations. Several individuals were identified who type genotypically for A*2402, but are serologically null for the HLA-A24 Ag. Sequencing and transfection of genomic DNA fragments containing null and wild-type A*2402 alleles, and the related A*2301 allele, revealed three different null alleles (A*2409N, A*2411N, and A*2402(low)), each of which differs from A*2402 by a single nucleotide change within the 6.7-kb sequence. The A*2301 and A*2402 sequences differ by no substitutions additional to those previously determined for the 1.1-kb cDNA. In exon 4, A*2409N has an in-frame stop codon, while A*2411N has a nucleotide insertion that alters the reading frame, causing premature termination. A*2402(low) has a nucleotide substitution near the splice acceptor site for intron 2 that impairs the production of correctly spliced mRNA. For A*2409N and A*2411N, mRNA is undetectable by Northern analysis, whereas A*2402(low) produces a low level of mRNA and a concomitant amount of normal A*2402 protein at the cell surface. The protein expressed from the A*2402(low) allele is sufficient to stimulate an alloreactive T cell response. On a background of unexpected sequence homogeneity, the single nucleotide changes in the A*2409N, A*2411, and A*2402(low) alleles have dramatic effects upon gene expression and are of likely importance for HLA matching in clinical transplantation. Segregation of at least three independently inactivated A*2402 alleles in human populations raises the possibility that loss of A*2402 may be the result of natural selection.

The complete sequence of a new HLA-C allele, Cw*1701, was determined from a South African Zulu individual. Unique features that distinguish Cw*1701 from other HLA-C alleles include multiple point substitutions and an 18 nucleotide insertion in exon 5, which encodes the transmembrane domain. In a phylogenetic analysis of HLA-C sequences, Cw*1701 forms a third, distinct allelic lineage. A comparison of the transmembrane domain of Cw*1701 with other HLA-B and -C alleles reveals that duplications and deletions have been common in the evolution of these loci. A polymerase chain reaction based typing method was used to determine the distribution of this unusual allele in human populations. In contrast to the other two lineages of HLA-C alleles, the Cw*17 lineage is found at high frequencies only in populations of African descent. In addition, the HLA-B/Cw*17 haplotype diversity is higher in Africa.

The sequence of a new B*39 allele has been identified in a South African Zulu individual. This allele designated B*3910, differs at two nucleotide positions (246 and 272) from B*39011. The difference at position 246 is silent, while that at position 272 results in an amino acid change from cysteine (B*39011) to tyrosine (B*3910). As these same differences are found in other HLA-B alleles, they were probably introduced into the B*3910 sequence by a short gene conversion event with another allele. This finding provides further evidence for the diversification of HLA-B allelic sequences via recombination.

The peptide-binding specificity of HLA-Cw*0304 was determined. Sequence analysis of endogenously-bound peptides isolated from Cw*0304 expressed by LCL 721.221 (221 for short) cells transfected with Cw*0304 cDNA revealed this class I allotype preferentially binds peptides possessing alanine at position 2 and leucine or methionine at the C-terminus. One peptide isolated from Cw*0304 expressed by 221 cells has sequence identity to residues 116-126 of HLA-E. Expression of HLA-E by 221 cells was confirmed by isolation of mRNA transcripts for HLA-E*0101 and detection of beta 2-microglobulin (beta 2-m)-associated HLA-E protein.

C. Tyler-Smith *, T. Zerjal , Y. Xue , R.S. Wells , W. Bao , S. Zhu , R. Qamar , Q. Ayub , A. Mohyuddin , S. Fu , P. Li , R. Du , H. Yang , S.Q. Mehdi , N. Yuldasheva , R. Ruzibakiev , M.E. Hurles , E. Robinson , T. Gerelsaikhan , B. Dashnyam h Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK Department of Medical Biology, Harbin Medical University, China Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK Institute of Genetics, Chinese Academy of Sciences, China Biomedical and Genetic Engineering Laboratories, Islamabad, Pakistan Institute of Immunology, Academy of Sciences, Tashkent, Uzbekistan McDonald Institute, University of Cambridge, Cambridge, UK Institute of Biotechnology, Mongolian Academy of Sciences, Ulaanbaatar, Mongolia

A patient with benign cellular naevi with unusual target-like morphology is described. Histological and histochemical examination of the lesions showed Dopa oxidase positive cells in the epidermal portion of the tumour but only the naevus cells and keratinocytes at the periphery of the tumour stained for melanin. It is suggested that failure of melanin synthesis is the cause of the target-like appearance.

This report focuses on the regulation of murine melanoma by the embryonic skin. A surgical technique was developed to allow injection of B16 melanoma cells into the embryo in utero. A significant decrease in incidence of tumors was noted, which correlated with the time of arrival of normally migrating premelanocytes into the skin. Media were conditioned from skin explanted at the time premelanocytes arrive in it; these media inhibited the growth of melanoma cells in vitro. Under optimal conditions the growth of melanoma cells ceased; the cells had altered morphology and failed to proliferate when placed in fresh growth media.

Evidence is presented that type IV of the Ehlers-Danlos syndrome (EDS IV) is genetically variable. A benign autosomal dominant form and two autosomal recessive variants are described with clinical and biochemical features that are distinct from classical acrogeria.

SUMMARY The BIDS syndrome comprises brittle hair, intellectual impairment, decreased fertility and short stature. Hair from patients with the BIDS syndrome shows disordered cuticular scales on scanning electronmicroscopy, alternate bright and dark banding on polarizing microscopy and low sulphur content. This report describes a case in which ichthyosis occurred in combination with the other features of the BIDS syndrome.

The treatment of the more severe types of congenital ichthyosis represents a major problem in paediatric dermatology. Of these disorders the greatest difficulties are presented by bullous ichthyosiform erythroderma (syn. epidermolytic hyperkeratosis) and by non-bullous ichthyosiform eyrthro-derma (syn. lamellar ichthyosis). Intensive topical therapy with emollients and keratolytics provides only limited and short-lived relief in the worst affected cases, and though high dosage oral vitamin A and later oral retinoic acid were definitely beneficial, this effect was nullified by the considerable toxicity of both agents. When etretinate became available, it was hoped that a superior therapeutic index would be achieved, and early reports1,2 of its value in these ichthyoses were encouraging. As far as we are aware, all trials of etretinate in the ichthyoses have so far been conducted on an open basis, at least partly because the epithelial effects of the drug make it difficult to maintain strictly double-blind conditions. Another problem in trial design is the need for careful tailoring of the dose for the individual patient. We nevertheless believed that the benefits of etretinate in the ichthyoses did require confirmation in a properly controlled study, and employed a novel trial design in an attempt to overcome these problems.

Twenty-seven per cent of atopic patients initially presenting with infantile eczema or hay fever were defective for yeast opsonization and 18% had low levels of C2; these deficiencies were mutually exclusive, suggesting that they are primary. Both defects were associated with each of four different atopic syndromes, some of which were related to certain HLA haplotypes.

Previous experiments have demonstrated specific inhibition of tumor formation after neuroblastoma cells were injected into fragments of 8.5- to 9.5-day embryonic tissue (A.H. Podesta et al. Proc. Natl. Acad. Sci. USA, 81:7608-7611, 1984). The effect was localized to the somite and appeared specific for neuroblastoma as opposed to a variety of other tumor types. This regulation of neuroblastoma cells was believed to reflect an underlying event in the development of migrating embryonic neuroblasts. The current experiments were done to determine the effect on regulation with further embryonic development. The results indicated that later embryos (13 to 17 days of gestation) have a widespread inhibitory effect in all tissues tested, including the adrenal gland, testis, kidney, liver, limb bud, and heart. In contrast a leukemia cell line was not affected by any of these tissues. In organ culture demonstrable colony formation by neuroblastoma was likewise inhibited, and conditioned media from one of these embryonic sources (limb bud) slowed but did not abrogate growth of neuroblastoma cells.

The purpose of this study was to determine whether the neurula stage mouse embryo can regulate tumor formation of C-1300-3 neuroblastoma cells. Five neuroblastoma cells were injected into the second somite of neurula stage embryos, and their ability to form tumors was tested, 24 hr later, by transplanting the portion of the embryo containing the cancer cells into the testes of adult mice. Only one-third the number of tumors was obtained in comparison with controls in which (i) five neuroblastoma cells were injected into blocks of liver tissue that were then transplanted into the testes of adult animals or (ii) five C-1300-3 neuroblastoma cells were injected directly into the testes. When five C-1300-3 cells were injected into somites, which had been dissected from embryos, and the injected somites were placed in animals, significantly fewer tumors were obtained in relationship with controls. Although it is not known whether the neuroblastoma cells are induced to differentiate or are killed by the embryonic tissue, the effect appeared to be specific because the tumor-forming ability of L1210 leukemia, B-16 melanoma, embryonal carcinoma 247, and a parietal yolk sac carcinoma was unaffected by somites.

Cultured mouse cells were tested for tumorigenicity in nude mice with both a conventional assay (injection of cell suspensions) and a new test involving implantation of cells grown on gelatin sponges. Sublines of Balb/3T3 cells, obtained from different sources, varied in their tumorigenic potential with either assay. One subline (A) formed distinctive precancerous nodules only in the sponge assay; these nodules often became progressive after a latent period of 3-4 months. However, suspensions of cells of this subline also caused tumors after a similar latent period, but no nodular phase preceded tumor formation. Another subline of Balb/3T3 (M) has failed to form tumors in either assay. The Balb/3T3 sublines did not differ in vitro properties, such as low saturation density, failure to grow in methylcellulose, and monolayer morphology. A second experimental approach involved tests on nude BALB/c mouse-embryo fibroblasts at various passage levels. The cells were passaged from primary culture, through crisis, to heteroploid, established cell lines. Tumorigenicity was demonstrable earlier in the sponge assay, at which time in vitro parameters putatively associated with malignant behavior were unchanged. Possible relationships with the in vivo phenomenon of solid-surface sarcomagenesis are discussed.

An assay to determine the mechanism of regulation of embryonal carcinoma cells by the blastocyst, which is based on a comparison of tumors produced when the cancer cells are cloned alone or after incorporation into blastocysts, was refined by labeling embryonal carcinoma cells with fluorescent microspheres and by following their fate after injection into the blastocysts. Through the use of the new techniques, it was observed that cells of one line of nullipotent embryonal carcinoma were controlled at the 50% level, those from another were not controlled, and those from a multipotent but undifferentiated line were controlled in almost absolute fashion. Single Sarcoma 180 of L1210 leukemia cells were not controlled when injected into the blastocele, but C1300 neuroblastoma cells were partially controlled. None of these tumors have a normal cellular counterpart in the blastocyst, as does embryonal carcinoma, but neurulation follows blastulation by only a few days, so that the neuroblastoma cells may be regulated at that time. Parietal yolk sac carcinoma cells, which have a counterpart in the late blastocyst, were not controlled. On the basis of these data, it is postulated that, if one embryonic field can regulate its closely related cancer, then there may be an embryonic field capable of regulating each carcinoma.