Silicon isotope constraints on terrestrial planet accretion.

Understanding the nature and origin of the precursor material to terrestrial planets is key to deciphering the mechanisms and timescales of planet formation1. Nucleosynthetic variability among rocky Solar System bodies can trace the composition of planetary building blocks2-5. Here we report the nucleosynthetic composition of silicon (µ30Si), the most abundant refractory planet-building element, in primitive and differentiated meteorites to identify terrestrial planet precursors. Inner Solar System differentiated bodies, including Mars, record µ30Si deficits of -11.0 ± 3.2 parts per million to -5.8 ± 3.0 parts per million whereas non-carbonaceous and carbonaceous chondrites show µ30Si excesses from 7.4 ± 4.3 parts per million to 32.8 ± 2.0 parts per million relative to Earth. This establishes that chondritic bodies are not planetary building blocks. Rather, material akin to early-formed differentiated asteroids must represent a major planetary constituent. The µ30Si values of asteroidal bodies correlate with their accretion ages, reflecting progressive admixing of a µ30Si-rich outer Solar System material to an initially µ30Si-poor inner disk. Mars' formation before chondrite parent bodies is necessary to avoid incorporation of µ30Si-rich material. In contrast, Earth's µ30Si composition necessitates admixing of 26 ± 9 per cent of µ30Si-rich outer Solar System material to its precursors. The µ30Si compositions of Mars and proto-Earth are consistent with their rapid formation by collisional growth and pebble accretion less than three million years after Solar System formation. Finally, Earth's nucleosynthetic composition for s-process sensitive (molybdenum and zirconium) and siderophile (nickel) tracers are consistent with pebble accretion when volatility-driven processes during accretion and the Moon-forming impact are carefully evaluated.

Non-target analysis of Danish wastewater treatment plant effluent: Statistical analysis of chemical fingerprinting as a step toward a future monitoring tool.

In an attempt to discover and characterize the plethora of xenobiotic substances, this study investigates chemical compounds released into the environment with wastewater effluents. A novel non-targeted screening methodology based on ultra-high resolution Orbitrap mass spectrometry and nanoflow ultra-high performance liquid chromatography together with a newly optimized data-processing pipeline were applied to effluent samples from two state-of-the-art and one small wastewater treatment facility. In total, 785 molecular structures were obtained, of which 38 were identified as single compounds, while 480 structures were identified at a putative level. Most of these substances were therapeutics and drugs, present as parent compounds and metabolites. Using R packages Phyloseq and MetacodeR, originally developed for bioinformatics, significant differences in xenobiotic presence in the wastewater effluents between the three sites were demonstrated.

3D Sensors for Sewer Inspection: A Quantitative Review and Analysis.

Automating inspection of critical infrastructure such as sewer systems will help utilities optimize maintenance and replacement schedules. The current inspection process consists of manual reviews of video as an operator controls a sewer inspection vehicle remotely. The process is slow, labor-intensive, and expensive and presents a huge potential for automation. With this work, we address a central component of the next generation of robotic inspection of sewers, namely the choice of 3D sensing technology. We investigate three prominent techniques for 3D vision: passive stereo, active stereo, and time-of-flight (ToF). The Realsense D435 camera is chosen as the representative of the first two techniques wheres the PMD CamBoard pico flexx represents ToF. The 3D reconstruction performance of the sensors is assessed in both a laboratory setup and in an outdoor above-ground setup. The acquired point clouds from the sensors are compared with reference 3D models using the cloud-to-mesh metric. The reconstruction performance of the sensors is tested with respect to different illuminance levels and different levels of water in the pipes. The results of the tests show that the ToF-based point cloud from the pico flexx is superior to the output of the active and passive stereo cameras.

Screening for retinopathy in children with type 1 diabetes in Denmark.

BACKGROUND/OBJECTIVE: Children with type 1 diabetes (T1D) are screened regularly for retinopathy with fundus photography to prevent visual impairment. According to Danish national guidelines, screening should take place at age 12, 15, and 18 years after minimum 3 years of diabetes. As glycemic control has improved, prevalence of retinopathy is expected to be decreased. The aim of this study is to investigate the prevalence, degree, and progression of retinopathy in children with T1D and to explore if screening at 12 years is currently indicated in Denmark. METHODS: Data on all Danish children with onset of T1D from 2003 to 2013 (n = 2943) were collected from the "DanDiabKids" registry. For children with registered screenings (n = 2382), prevalence of retinopathy at 12, 15, and 18 years was determined. In children with retinopathy, subsequent screenings were studied to reveal if retinopathy was persistent or temporary. RESULTS: Prevalence of retinopathy at 12, 15, and 18 years was 0.9%, 2.3%, and 3.1%, respectively. Minimal background retinopathy was seen in over 90% and 100% at 12 years. In available re-screenings, retinopathy resolved spontaneously in 87.5% of all cases and 100% of cases at 12 years. CONCLUSIONS: The prevalence of retinopathy in Danish children with T1D was low. At 12 years, prevalence was 0.9% and exclusively minimal background retinopathy with 100% remission in re-screenings. Thus, screening at this age does not seem to have significant clinical relevance. We propose more individualized screening selection before the age of 15.

An abundance of small exoplanets around stars with a wide range of metallicities.

The abundance of heavy elements (metallicity) in the photospheres of stars similar to the Sun provides a 'fossil' record of the chemical composition of the initial protoplanetary disk. Metal-rich stars are much more likely to harbour gas giant planets, supporting the model that planets form by accumulation of dust and ice particles. Recent ground-based surveys suggest that this correlation is weakened for Neptunian-sized planets. However, how the relationship between size and metallicity extends into the regime of terrestrial-sized exoplanets is unknown. Here we report spectroscopic metallicities of the host stars of 226 small exoplanet candidates discovered by NASA's Kepler mission, including objects that are comparable in size to the terrestrial planets in the Solar System. We find that planets with radii less than four Earth radii form around host stars with a wide range of metallicities (but on average a metallicity close to that of the Sun), whereas large planets preferentially form around stars with higher metallicities. This observation suggests that terrestrial planets may be widespread in the disk of the Galaxy, with no special requirement of enhanced metallicity for their formation.

Children and adolescents in the Psychiatric Emergency Department: a 10-year survey in Copenhagen County.

BACKGROUND: Knowledge on psychiatric emergencies in children and adolescents is limited. The Psychiatric Emergency Departments (PED) in Copenhagen enable the acute examination of children and adolescents 24 h a day, 7 days a week. However, very little is known about who presents to the PED, and the reason for their visit. AIM: To describe the prevalence and characteristics of presentations in PED and treatment provided. METHODS: A retrospective population based study comprising data of more than 4000 visitors presenting to PED from 2001-2010. In 2003 and 2006, two randomly chosen years, a more thorough analysis was performed, based on the individual emergency charts. Inter-rater reliability was high. RESULTS: Visits increased nearly threefold during the period. Symptom score for 2003 and 2006 revealed that more than one third of the visitors had suicidal ideation. Depressive and anxiety symptoms together with suicidal ideation rose significantly (P < 0.001). Psychoses and suicidal attempts remained unchanged. In one third of the visits, the discharge diagnosis was anxiety and stress-related disorders, followed by personality, behavioural and emotional disorders. Between 15% and 20% of the visits resulted in admission and more than 50% in referral for outpatient follow-up. CONCLUSIONS: The number of presenting psychiatric emergencies has increased over the last 10 years. Comparing symptoms from 2003 and 2006 showed a significant rise in their severity. This study highlights the need for 24-h access for acute evaluation by physicians skilled in child and adolescent psychiatry, and raises concern that the severity could increase.

Cyanobacterial blooms in surface waters - Nature-based solutions, cyanotoxins and their biotransformation products.

Cyanobacterial blooms are expected to become more frequent and severe in surface water reservoirs due to climate change and ecosystem degradation. It is an emerging challenge that especially countries relying on surface water supplies will face. Nature-based solutions (NBS) like constructed wetlands and biofilters can be used for cyanotoxin remediation. Both technologies are reviewed and critically assessed for different types of water resources. The available information on cyanotoxins (bio)transformation products (TPs) is reviewed to point out the potential research gaps and to disclose the most reliable enzymatic degradation pathways. Knowledge gaps were found, such as information on the performance of the revised NBS in pilot and full scales, the removal processes covering different cyanotoxins (besides the most widely studied microcystin-LR), and the difficulties for real-world implementation of technologies proposed in the literature. Also, most studies focus on bacterial degradation processes while fungi have been completely overlooked. This review also presents an up-to-date overview of the transformation of cyanotoxins, where degradation product data was compiled in a unified library of 22 metabolites for microcystins (MCs), 7 for cylindrospermopsin (CYN) and 10 for nodularin (NOD), most of them reported only in a single study. Major gaps are the lack of environmentally relevant studies with TPs in pilot and full- scale treatment systems, information on TP's toxicity, as well as limited knowledge of environmentally relevant degradation pathways. NBS have the potential to mitigate cyanotoxins in recreational and irrigation waters, enabling the water-energy-food nexus and avoiding the degradability of the ecosystems.

Fungal removal of cyanotoxins in constructed wetlands: The forgotten degraders.

Harmful cyanobacterial blooms have increased globally, releasing hazardous cyanotoxins that threaten the safety of water resources. Constructed wetlands (CWs) are a nature-based and low-cost solution to purify and remove cyanotoxins from water. However, bio-mechanistic understanding of the biotransformation processes expected to drive cyanotoxin removal in such systems is poor, and primarily focused on bacteria. Thus, the present study aimed at exploring the fungal contribution to microcystin-LR and cylindrospermopsin biodegradation in CWs. Based on CW mesocosms, two experimental approaches were taken: a) amplicon sequencing studies were conducted to investigate the involvement of the fungal community; and b) CW fungal isolates were tested for their microcystin-LR and cylindrospermopsin degradation capabilities. The data uncovered effects of seasonality (spring or summer), cyanotoxin exposure, vegetation (unplanted, Juncus effusus or Phragmites australis) and substratum (sand or gravel) on the fungal community structure. Additionally, the arbuscular mycorrhizal fungus Rhizophagus and the endophyte Myrmecridium showed positive correlations with cyanotoxin removal. Fungal isolates revealed microcystin-LR-removal potentials of approximately 25 % in in vitro biodegradation experiments, while the extracellular chemical fingerprint of the cultures suggested a potential intracellular metabolization. The results from this study may help us understand the fungal contribution to cyanotoxin removal, as well as their ecology in CWs.

Constructed wetland mesocosms improve the biodegradation of microcystin-LR and cylindrospermopsin by indigenous bacterial consortia.

Cyanobacterial blooms releasing harmful cyanotoxins, such as microcystin (MC) and cylindrospermopsin (CYN), are prominent threats to human and animal health. Constructed wetlands (CW) may be a nature-based solution for bioremediation of lake surface water containing cyanotoxins, due to its low-cost requirement of infrastructure and environmentally friendly operation. There is recent evidence that microcystin-LR (MC-LR) can efficiently be removed in CW microcosms where CYN degradation in CW is unknown. Likewise, the mechanistic background regarding cyanotoxins transformation in CW is not yet elucidated. In the present study, the objective was to compare MC-LR and CYN degradation efficiencies by two similar microbial communities obtained from CW mesocosms, by two different experiments setup: 1) in vitro batch experiment in serum bottles with an introduced CW community, and 2) degradation in CW mesocosms. In experiment 1) MC-LR and CYN were spiked at 100 µg L-1 and in experiment 2) 200 µg L-1 were spiked. Results showed that MC-LR was degraded to ≤1 µg L-1 within seven days in both experiments. However, with a markedly higher degradation rate constant in the CW mesocosms (0.18 day-1 and 0.75 day-1, respectively). No CYN removal was detected in the in vitro incubations, whereas around 50 % of the spiked CYN was removed in the CW mesocosms. The microbial community responded markedly to the cyanotoxin treatment, with the most prominent increase of bacteria affiliated with Methylophilaceae (order: Methylophilales, phylum: Proteobacteria). The results strongly indicate that CWs can develop an active microbial community capable of efficient removal of MC-LR and CYN. However, the CW operational conditions need to be optimized to achieve a full CYN degradation. To the best of our knowledge, this study is the first to report the ability of CW mesocosms to degrade CYN.

Rapid planetesimal formation in turbulent circumstellar disks.

During the initial stages of planet formation in circumstellar gas disks, dust grains collide and build up larger and larger bodies. How this process continues from metre-sized boulders to kilometre-scale planetesimals is a major unsolved problem: boulders are expected to stick together poorly, and to spiral into the protostar in a few hundred orbits owing to a 'headwind' from the slower rotating gas. Gravitational collapse of the solid component has been suggested to overcome this barrier. But even low levels of turbulence will inhibit sedimentation of solids to a sufficiently dense midplane layer, and turbulence must be present to explain observed gas accretion in protostellar disks. Here we report that boulders can undergo efficient gravitational collapse in locally overdense regions in the midplane of the disk. The boulders concentrate initially in transient high pressure regions in the turbulent gas, and these concentrations are augmented a further order of magnitude by a streaming instability driven by the relative flow of gas and solids. We find that gravitationally bound clusters form with masses comparable to dwarf planets and containing a distribution of boulder sizes. Gravitational collapse happens much faster than radial drift, offering a possible path to planetesimal formation in accreting circumstellar disks.

Composting reduces the risks of antibiotic resistance genes in maize seeds posed by gentamicin fermentation waste.

Using high-throughput quantitative PCR and next generation sequencing, the impact of land application of raw and composted gentamicin fermentation waste (GFW) on antibiotic resistance genes (ARGs) in maize seeds was studied in a three-year field trial. The raw and composted GFW changed both the bacterial community composition and the ARGs diversity in the maize seeds compared to non-amended controls and chemical fertilizer. The abundance of ARGs after raw GFW amendment was significantly higher than other treatments because of a high abundance of aadA1, qacEdeltal and aph(2')-Id-02; probably induced by gentamicin selection pressure in maize tissues. Meanwhile, the potential host of these three ARGs, pathogenic bacteria Tenacibaculum, also increased significantly in maize seeds after the application of raw GFW. But our result proved that composting could weaken the risk posed by GFW. We further reveal that the key biotic driver for shaping the ARG profiles in maize seeds is bacterial community followed by heavy metal resistance genes, and ARGs are more likely located on bacterial chromosomes. Our findings provide new insight into ARGs dispersal mechanism in maize seeds after long-term GFW application, demonstrate the potential benefits of composting the GFW to reduce risks as well as the potential efficient management method to GFW.

Video Transformers: A Survey.

Transformer models have shown great success handling long-range interactions, making them a promising tool for modeling video. However, they lack inductive biases and scale quadratically with input length. These limitations are further exacerbated when dealing with the high dimensionality introduced by the temporal dimension. While there are surveys analyzing the advances of Transformers for vision, none focus on an in-depth analysis of video-specific designs. In this survey, we analyze the main contributions and trends of works leveraging Transformers to model video. Specifically, we delve into how videos are handled at the input level first. Then, we study the architectural changes made to deal with video more efficiently, reduce redundancy, re-introduce useful inductive biases, and capture long-term temporal dynamics. In addition, we provide an overview of different training regimes and explore effective self-supervised learning strategies for video. Finally, we conduct a performance comparison on the most common benchmark for Video Transformers (i.e., action classification), finding them to outperform 3D ConvNets even with less computational complexity.

Alkalilactibacillus ikkensis, gen. nov., sp. nov., a novel enzyme-producing bacterium from a cold and alkaline environment in Greenland.

Three novel Gram-positive, endospore-forming bacteria were isolated from a cold and alkaline environment. Phylogenetic analysis showed that the strains were almost identical, and that they were related to Natronobacillus azotifigens 24KS-1(T) (95.8% identity), Paraliobacillus quinghaiensis YIM-C158(T) (95.1%), Paraliobacillus ryukyuensis O15-7(T) (94.5%), and Halolactibacillus miurensis M23-1(T) (93.9%). The isolates produced amylase, α-galactosidase, ß-galactosidase, and ß-glucuronidase, and showed optimal growth at pH 10, at 20°C, and at 2-8% (w/v) NaCl. Major fatty acids were C(14:0) (10.6-11.6%), anteiso-C(15:0) (25.7-32.7%), C(16:1) ω11c (12.2-16.0%), and C(16:0) (14.0-20.4%). The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol, and meso-diaminopimelic acid was found in the cell-wall peptidoglycan. The G+C content was 38.4%. DNA-DNA hybridization between strain GCM68(T) and H. miurensis M23-1(T) was 32.4%, while hybridization to N. azotifigens 24KS-1(T), Amphibacillus tropicus Z-7792(T), and Paraliobacillus ryukyuensis O15-7(T) was below 30%. The phylogenetic analysis and G+C content place strain GCM68(T) in relation to species belonging to Bacillus rRNA group 1, but phylogenetic and physiologic data combined with chemotaxonomic analyses support our proposal for a new genus, Alkalilactibacillus, gen. nov., with the novel species Alkalilactibacillus ikkensis, sp. nov. (type strain is GCM68(T) = DSM 19937 = LMG 24405).

Necrotizing enterocolitis after red blood cell transfusion in preterm infants with patent ductus arteriosus: a case series.

AIM: Both patent ductus arteriosus (PDA) and packed red blood cell (PRBC) transfusion are risk factors for necrotizing enterocolitis (NEC). The combination of PDA and PRBC transfusion may have a synergistic effect on the intestinal circulation. METHODS: We present four cases of NEC in very low birth weight (VLBW) infants within 14 h after PRBC transfusion. RESULTS: All infants were growing on full enteral feeding, and they all had a PDA. CONCLUSION: We are concerned that the simultaneous presence of a PDA and PRBC transfusion in VLBW infants may place the infant at even greater risk of NEC than each of these factors alone.

Nano-silver induces dose-response effects on the nematode Caenorhabditis elegans.

Toxicity of nano-formulated silver to eukaryotes was assessed by exposing nematodes (Caenorhabditis elegans) to two types of silver nanoparticles (AgNPs): with average primary particle diameters of 1 nm (AgNP1) and 28nm (AgNP28, PVP coated), respectively. Tests were performed with and without presence of Escherichia coli to evaluate how the presence of a food bacterium affects the AgNP toxicity. A pre-exposure experiment was also conducted with nematodes pre-exposed to 0 and 1mgAgNPL(-1), respectively, for 20 h prior to exposure at higher concentrations of AgNP. Both AgNP1 and AgNP28 showed adverse dose-response effects and mortality on C. elegans. LC(50) for AgNP28 was lower than for AgNP1 and, hence, at the present test conditions the PVP-coated AgNP28 was more toxic than AgNP1. Including E. coli in the test medium as a food source increased AgNPs toxicity towards nematodes compared to when bacteria were not present. Pre-exposure to a low-level AgNP1 concentration made the nematodes slightly more sensitive to further exposure at higher concentrations compared to no pre-exposure, indicating that nematodes have no efficient physiological ability to counteract nano-silver toxicity by acclimation. The amount of dissolved Ag(+) was 0.18 to 0.21 mg L(-1) after 20 h at the highest AgNP1 (10 mg L(-1)) and AgNP28 (3 mg L(-1)) doses in the exposure medium, respectively. The upper limit of Ag(+) solubility cannot immediately explain the dose-response-related toxic effects of the AgNP nor the difference between AgNP1 and AgNP28. Higher toxicity of AgNP28 than AgNP1 may be explained by a combination of effects of coating, Ag-solubility and higher uptake rates due to agglomeration into µm-size agglomerates in the exposure medium.

Natural separation of two primordial planetary reservoirs in an expanding solar protoplanetary disk.

Meteorites display an isotopic composition dichotomy between noncarbonaceous (NC) and carbonaceous (CC) groups, indicating that planetesimal formation in the solar protoplanetary disk occurred in two distinct reservoirs. The prevailing view is that a rapidly formed Jupiter acted as a barrier between these reservoirs. We show a fundamental inconsistency in this model: If Jupiter is an efficient blocker of drifting pebbles, then the interior NC reservoir is depleted by radial drift within a few hundred thousand years. If Jupiter lets material pass it, then the two reservoirs will be mixed. Instead, we demonstrate that the arrival of the CC pebbles in the inner disk is delayed for several million years by the viscous expansion of the protoplanetary disk. Our results support the hypothesis that Jupiter formed in the outer disk (>10 astronomical units) and allowed a considerable amount of CC material to pass it and become accreted by the terrestrial planets.

Greenland Ice Sheet Surfaces Colonized by Microbial Communities Emit Volatile Organic Compounds.

Volatile organic compounds (VOCs) are emitted by organisms for a range of physiological and ecological reasons. They play an important role in biosphere-atmosphere interactions and contribute to the formation of atmospheric secondary aerosols. The Greenland ice sheet is home to a variety of microbial communities, including highly abundant glacier ice algae, yet nothing is known about the VOCs emitted by glacial communities. For the first time, we present VOC emissions from supraglacial habitats colonized by active microbial communities on the southern Greenland ice sheet during July 2020. Emissions of C5-C30 compounds from bare ice, cryoconite holes, and red snow were collected using a push-pull chamber active sampling system. A total of 92 compounds were detected, yielding mean total VOC emission rates of 3.97 ± 0.70 µg m-2 h-1 from bare ice surfaces (n = 31), 1.63 ± 0.13 µg m-2 h-1 from cryoconite holes (n = 4), and 0.92 ± 0.08 µg m-2 h-1 from red snow (n = 2). No correlations were found between VOC emissions and ice surface algal counts, but a weak positive correlation (r = 0.43, p = 0.015, n = 31) between VOC emission rates from bare ice surfaces and incoming shortwave radiation was found. We propose that this may be due to the stress that high solar irradiance causes in bare ice microbial communities. Acetophenone, benzaldehyde, and phenylmaleic anhydride, all of which have reported antifungal activity, accounted for 51.1 ± 11.7% of emissions from bare ice surfaces, indicating a potential defense strategy against fungal infections. Greenland ice sheet microbial habitats are, hence, potential sources of VOCs that may play a role in supraglacial microbial interactions, as well as local atmospheric chemistry, and merit future research efforts.

Effects of pristine microplastics and nanoplastics on soil invertebrates: A systematic review and meta-analysis of available data.

In laboratory studies, microplastics and/or nanoplastics (MPs/NPs) have been shown to cause a variety of ecotoxicological effects on soil invertebrates. Existing data on the effects of these plastic debris on biological functions and physiological systems, showed a great variability among studies. Thus, how soil invertebrates respond to different types, shapes, sizes and concentrations of pristine MPs/NPs remains to be further characterized. The present work is an up-to-date review on quantitative and qualitative data on the effects of pristine MPs/NPs on soil invertebrates in laboratory conditions. Research priorities are also discussed. Out of a total of 1061 biological endpoints investigated in 56 studies, 49% were significantly affected after exposed to pristine MPs/NPs. The polymers with chloro and phenyl groups had more negative impacts on soil invertebrates than other polymers. Most studies used earthworm and nematode species as model organisms. For nematodes, the impact of MPs/NPs seemed to be concentration-dependent and higher concentrations of pristine MPs/NPs appeared to have more adverse impacts on biological functions and physiological systems, but this trend was not confirmed in earthworms. Meta-analysis revealed that pristine MP/NP concentrations higher than 1 g kg-1 (in soil) may decrease growth and survival of earthworms, while a concentration higher than 1 µg L-1 (in water) may affect nematode reproductive fitness.

A pebble accretion model for the formation of the terrestrial planets in the Solar System.

Pebbles of millimeter sizes are abundant in protoplanetary discs around young stars. Chondrules inside primitive meteorites-formed by melting of dust aggregate pebbles or in impacts between planetesimals-have similar sizes. The role of pebble accretion for terrestrial planet formation is nevertheless unclear. Here, we present a model where inward-drifting pebbles feed the growth of terrestrial planets. The masses and orbits of Venus, Earth, Theia (which later collided with Earth to form the Moon), and Mars are all consistent with pebble accretion onto protoplanets that formed around Mars' orbit and migrated to their final positions while growing. The isotopic compositions of Earth and Mars are matched qualitatively by accretion of two generations of pebbles, carrying distinct isotopic signatures. Last, we show that the water and carbon budget of Earth can be delivered by pebbles from the early generation before the gas envelope became hot enough to vaporize volatiles.

Mutations in the VNTR of the carboxyl-ester lipase gene (CEL) are a rare cause of monogenic diabetes.

We have previously shown that heterozygous single-base deletions in the carboxyl-ester lipase (CEL) gene cause exocrine and endocrine pancreatic dysfunction in two multigenerational families. These deletions were found in the first and fourth repeats of a variable number of tandem repeats (VNTR), which has proven challenging to sequence due to high GC-content and considerable length variation. We have therefore developed a screening method consisting of a multiplex PCR followed by fragment analysis. The method detected putative disease-causing insertions and deletions in the proximal repeats of the VNTR, and determined the VNTR-length of each allele. When blindly testing 56 members of the two families with known single-base deletions in the CEL VNTR, the method correctly assessed the mutation carriers. Screening of 241 probands from suspected maturity-onset diabetes of the young (MODY) families negative for mutations in known MODY genes (95 individuals from Denmark and 146 individuals from UK) revealed no deletions in the proximal repeats of the CEL VNTR. However, we found one Danish patient with a short, novel CEL allele containing only three VNTR repeats (normal range 7-23 in healthy controls). This allele co-segregated with diabetes or impaired glucose tolerance in the patient's family as six of seven mutation carriers were affected. We also identified individuals who had three copies of a complete CEL VNTR. In conclusion, the CEL gene is highly polymorphic, but mutations in CEL are likely to be a rare cause of monogenic diabetes.