Genome-wide association studies have uncovered thousands of common variants associated with human disease, but the contribution of rare variation to common disease remains relatively unexplored. The UK Biobank (UKB) contains detailed phenotypic data linked to medical records for approximately 500,000 participants, offering an unprecedented opportunity to evaluate the impact of rare variation on a broad collection of traits1,2. Here, we studied the relationships between rare protein-coding variants and 17,361 binary and 1,419 quantitative phenotypes using exome sequencing data from 269,171 UKB participants of European ancestry. Gene-based collapsing analyses revealed 1,703 statistically significant gene-phenotype associations for binary traits, with a median odds ratio of 12.4. Furthermore, 83% of these associations were undetectable via single variant association tests, emphasizing the power of gene-based collapsing analysis in the setting of high allelic heterogeneity. Gene-phenotype associations were also significantly enriched for loss-of-function-mediated traits and approved drug targets. Finally, we performed ancestry-specific and pan-ancestry collapsing analyses using exome sequencing data from 11,933 UKB participants of African, East Asian, or South Asian ancestry. Together, our results highlight a significant contribution of rare variants to common disease. Summary statistics are publicly available through an interactive portal (http://azphewas.com/).

Integrins are critical for hemostasis and thrombosis because they mediate both platelet adhesion and aggregation. Talin is an integrin-binding cytoplasmic adaptor that is a central organizer of focal adhesions, and loss of talin phenocopies integrin deletion in Drosophila . Here, we have examined the role of talin in mammalian integrin function in vivo by selectively disrupting the talin1 gene in mouse platelet precursor megakaryocytes. Talin null megakaryocytes produced circulating platelets that exhibited normal morphology yet manifested profoundly impaired hemostatic function. Specifi cally, platelet-specifi c deletion of talin1 led to spontaneous hemorrhage and pathological bleeding. Ex vivo and in vitro studies revealed that loss of talin1 resulted in dramatically impaired integrin ␣ IIb ␤ 3-mediated platelet aggregation and ␤ 1 integrin -mediated platelet adhesion. Furthermore, loss of talin1 strongly inhibited the activation of platelet ␤ 1 and ␤ 3 integrins in response to platelet agonists. These data establish that platelet talin plays a crucial role in hemostasis and provide the fi rst proof that talin is required for the activation and function of mammalian ␣ 2 ␤ 1 and ␣ IIb ␤ 3 integrins in vivo.

The author wishes to clarify that heterozygous mutations in the SCL34A1 gene have been described in only 2 individuals with nephrolithiasis, renal phosphate loss, and hypophosphatemia (Prié, D., et al. 2002. Nephrolithiasis and osteoporosis associated with hypophosphatemia caused by mutations in the type 2a sodium-phosphate cotransporter. N. Engl. J. Med. 347:983-991). After acceptance of this JCI Science in Medicine article for publication, 3 distinct mutations in NHERF1 were reported in 7 patients with renal phosphate loss and nephrolithiasis and/or bone demineralization (

Idiopathic pulmonary fibrosis (IPF) is a fatal disorder characterised by progressive, destructive lung scarring. Despite substantial progress, the genetic determinants of this disease remain incompletely defined. Using whole genome and whole exome sequencing data from 752 individuals with sporadic IPF and 119,055 UK Biobank controls, we performed a variant-level exome-wide association study (ExWAS) and gene-level collapsing analyses. Our variant-level analysis revealed a novel association between a rare missense variant in SPDL1 and IPF (NM_017785.5:g.169588475 G > A p.Arg20Gln; p = 2.4 × 10−7, odds ratio = 2.87, 95% confidence interval: 2.03–4.07). This signal was independently replicated in the FinnGen cohort, which contains 1028 cases and 196,986 controls (combined p = 2.2 × 10−20), firmly associating this variant as an IPF risk allele. SPDL1 encodes Spindly, a protein involved in mitotic checkpoint signalling during cell division that has not been previously described in fibrosis. To the best of our knowledge, these results highlight a novel mechanism underlying IPF, providing the potential for new therapeutic discoveries in a disease of great unmet need.

Wnt genes have been implicated in a range of developmental processes in the mouse including the patterning of the central nervous system and limbs. Reported here for the first time is the expression of Wnt2 in the early heart field of 7.5-8.5 dpc (days post-coitum) mouse embryos, making Wnt2 a potentially useful gene marker for the early stages of heart development. Expression was also detected in the allantois from 8.0 dpc and at later stages in the placenta and umbilicus. Mice deficient in Wnt2, generated by gene targeting, displayed runting and approximately 50% died perinatally. Histological analysis revealed alterations in the size and structure of placentas from these mice from 14.5 dpc. The placental defects were associated primarily with the labyrinthine zone and included oedema and tissue disruption and accumulation of maternal blood in large pools. There was also an apparent decrease in the number of foetal capillaries and an increase in the amount of fibrinoid material in the Wnt2 mutant placentas. These results suggest that Wnt2 is required for the proper vascularisation of the mouse placenta and the placental defects in Wnt2-deficient mice result in a reduction in birthweight and perinatal lethality.