Pseudosymmetric hetero-oligomers with three or more unique subunits with overall structural (but not sequence) symmetry play key roles in biology, and systematic approaches for generating such proteins de novo would provide new routes to controlling cell signaling and designing complex protein materials. However, the de novo design of protein hetero-oligomers with three or more distinct chains with nearly identical structures is a challenging unsolved problem because it requires the accurate design of multiple protein-protein interfaces simultaneously. Here, we describe a divide-and-conquer approach that breaks the multiple-interface design challenge into a set of more tractable symmetric single-interface redesign tasks, followed by structural recombination of the validated homo-oligomers into pseudosymmetric hetero-oligomers.
View Article and Find Full Text PDFBackground: Pleuropulmonary blastoma (PPB), the hallmark tumour associated with -related tumour predisposition, is characterised by an age-related progression from a cystic lesion (type I) to a high-grade sarcoma with mixed cystic and solid features (type II) or purely solid lesion (type III). Not all cystic PPBs progress; type Ir (regressed), hypothesised to represent regressed or non-progressed type I PPB, is an air-filled, cystic lesion lacking a primitive sarcomatous component. This study aims to evaluate the prevalence of non-progressed lung cysts detected by CT scan in adolescents and adults with germline pathogenic/likely pathogenic (P/LP) variants.
View Article and Find Full Text PDFGermline pathogenic variants in predispose individuals to develop a variety of benign and malignant tumors. Accurate variant curation and classification is essential for reliable diagnosis of -related tumor predisposition and identification of individuals who may benefit from surveillance. Since 2015, most labs have followed the American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG/AMP) sequence variant classification guidelines for germline variant curation.
View Article and Find Full Text PDFObjectives: Postdischarge phone calls can identify discharge errors and gather information following hospital-to-home transitions. This study used the multisite Project IMPACT (Improving Pediatric Patient Centered Care Transitions) dataset to identify factors associated with postdischarge phone call attempt and connectivity.
Methods: This study included 0- to 18-year-old patients discharged from 4 sites between January 2014 and December 2017.
Purpose: Fanconi anemia (FA) is a cancer-prone inherited bone marrow failure syndrome caused by biallelic pathogenic variants in one of >22 genes in the FA/BRCA DNA repair pathway. A major concern is whether the risk of cancer is increased in individuals with a single pathogenic FA gene variant.
Methods: We evaluated the risk of cancer in the relatives of patients with FA in the National Cancer Institute Inherited Bone Marrow Failure Syndrome cohort.
Importance: Genetic disorders are historically defined through phenotype-first approaches. However, risk estimates derived from phenotype-linked ascertainment may overestimate severity and penetrance. Pathogenic variants in DICER1 are associated with increased risks of rare and common neoplasms and thyroid disease in adults and children.
View Article and Find Full Text PDFPathogenic germline variants in DICER1 underlie an autosomal dominant, pleiotropic tumor-predisposition disorder. Murine models with the loss of DICER1 in hematopoietic stem cell progenitors demonstrate hematologic aberrations that include reductions in red and white blood cell counts, hemoglobin volume, and impaired maturation resulting in dysplasia. We investigated whether hematologic abnormalities such as those observed in DICER1-deficient mice were observed in humans with a pathogenic germline variant in DICER1.
View Article and Find Full Text PDFBackground: Several studies have reported conflicting evidence on the inclusion of testicular germ cell tumors (TGCT) in the DICER1 tumor-predisposition phenotype. We evaluated the relationship between DICER1 and TGCT by reviewing scrotal ultrasounds of males with pathogenic germline variants in DICER1 and queried exome data from TGCT-affected men for DICER1 variants.
Methodology: Fifty-four male DICER1-carriers and family controls (n=41) enrolled in the National Cancer Institute (NCI) DICER1 Natural History Study were offered scrotal ultrasounds.
Objective: Germline pathogenic variation in DICER1 underlies a tumor-predisposition disorder with increased risk for cervical embryonal rhabdomyosarcoma and ovarian sex-cord stromal tumors, particularly Sertoli-Leydig cell tumors. The gynecologic and reproductive health of these females has not yet been described.
Methods: All female subjects recruited from November 2011 to July 2018 participating in an epidemiologic study of families with pathogenic DICER1 germline variation were included in this cross-sectional analysis.
Background: Nasal chondromesenchymal hamartomas are benign, rare nasal tumors associated with pathogenic germline variation. They can be locally destructive and recurrent if not completely resected.
Methodology: In this single-center, case-control study, otorhinolaryngology evaluations and review of systems questionnaires of -carriers and controls enrolled in the Natural History Study at the National Cancer Institute were collected.
The black blow fly, Phormia regina (Meigen) (Diptera: Calliphoridae) is one of the most abundant carrion flies in North America. Calliphorids are important in agriculture and animal production, veterinary sciences, forensics and medical entomology. While the role of flies in the epidemiology of human and animal diseases is an active area of research, little is known about the microorganisms associated with these insects.
View Article and Find Full Text PDFTicks are second only to mosquitoes as vectors of disease to humans and animals. Tick host detection is mainly ascribed to Haller's organ, a complex sensory structure on the tick foreleg that detects odors, carbon dioxide and heat, but these host detection mechanisms are not well understood. There is anecdotal evidence that ticks and other ectoparasites are attracted to heat, but it has never been demonstrated that they use radiant heat to detect hosts at a distance.
View Article and Find Full Text PDFAm J Med Genet A
September 2019
Pathogenic germline variation in the microRNA processing gene DICER1 gives rise to an autosomal dominant, tumor-predisposition disorder. Conditional deletion of Dicer1 in murine dental epithelium shows that it controls tooth patterning, size, number, and shape. The human dental phenotype of people with germline pathogenic variation in DICER1 is unknown.
View Article and Find Full Text PDFPurpose: DICER1 syndrome is an autosomal-dominant, pleiotropic tumor-predisposition disorder caused by pathogenic germline variants in DICER1. We sought to quantify risk, hazard rates, and the probability of neoplasm incidence accounting for competing risks ("cumulative incidence") of neoplasms (benign and malignant) and standardized incidence ratios for malignant tumors in individuals with DICER1 pathogenic variation.
Patients And Methods: We combined data from three large cohorts of patients who carry germline pathogenic variation in DICER1.
Purpose: To characterize the ocular phenotype of DICER1 syndrome.
Design: Prospective, single-center, case-control study.
Participants: One hundred three patients with an identified germline pathogenic DICER1 variant (DICER1 carriers) and 69 family control participants underwent clinical and ophthalmic examination at the National Institutes of Health between 2011 and 2016.
Background: The DICER1 syndrome is a tumor-predisposition disorder caused by germline pathogenic variation in DICER1 and is associated with cystic nephroma and other renal neoplasms. Dicer1 mouse and rare human DICER1 syndrome case reports describe structural kidney and collecting system anomalies. We investigated renal function and the frequency of structural abnormalities of the kidney and collecting system in individuals with germline loss-of-function variants in DICER1.
View Article and Find Full Text PDFPathogenic germline variants cause a hereditary cancer predisposition syndrome with a variety of manifestations. In addition to conferring increased cancer risks for pleuropulmonary blastoma (PPB) and ovarian sex cord-stromal tumors, particularly Sertoli-Leydig cell tumor, individuals with pathogenic germline variants may also develop lung cysts, cystic nephroma, renal sarcoma and Wilms tumor, nodular hyperplasia of the thyroid, nasal chondromesenchymal hamartoma, ciliary body medulloepithelioma, genitourinary embryonal rhabdomyosarcoma, and brain tumors including pineoblastoma and pituitary blastoma. In May 2016, the International PPB Registry convened the inaugural International Symposium to develop consensus testing and surveillance and treatment recommendations.
View Article and Find Full Text PDFTicks are the vector of many human and animal diseases; and host detection is critical to this process. Ticks have a unique sensory structure located exclusively on the 1st pairs of legs; the fore-tarsal Haller's organ, not found in any other animals, presumed to function like the insect antennae in chemosensation but morphologically very different. The mechanism of tick chemoreception is unknown.
View Article and Find Full Text PDFThe Haller's organ (HO), unique to ticks and mites, is found only on the first tarsus of the front pair of legs. The organ has an unusual morphology consisting of an anterior pit (AP) with protruding sensilla and a posterior capsule (Cp). The current thinking is that the HO's main function is chemosensation analogous to the insect antennae, but the functionality of its atypical structure (exclusive to the Acari) is unexplained.
View Article and Find Full Text PDFContext: The risk of thyroid cancer and multinodular goiter (MNG) in DICER1 syndrome, a rare tumor-predisposition disorder, is unknown.
Objective: To quantify the risk of thyroid cancer and MNG in individuals with DICER1 syndrome.
Design: Family-based cohort study.
Purpose: Germ-line mutations in DICER1 increase the risk of various tumors, including pleuropulmonary blastoma. Macrocephaly and symmetric overgrowth have been reported in some, but not all, patients with mosaic DICER1 RNase IIIb mutations. The prevalence of these features in individuals with constitutional germ-line DICER1 mutations is unknown.
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