Citations

Pathogenic variants in KMT5B , a lysine methyltransferase, are associated with global developmental delay, macrocephaly, autism, and congenital anomalies (OMIM # 617788). Given the relatively recent discovery of this disorder, it has not been fully characterized. Deep phenotyping of the largest ( n = 43) patient cohort to date identified that hypotonia and congenital heart defects are prominent features that were previously not associated with this syndrome. Both missense variants and putative loss-of-function variants resulted in slow growth in patient-derived cell lines. KMT5B homozygous knockout mice were smaller in size than their wild-type littermates but did not have significantly smaller brains, suggesting relative macrocephaly, also noted as a prominent clinical feature. RNA sequencing of patient lymphoblasts and Kmt5b haploinsufficient mouse brains identified differentially expressed pathways associated with nervous system development and function including axon guidance signaling. Overall, we identified additional pathogenic variants and clinical features in KMT5B -related neurodevelopmental disorder and provide insights into the molecular mechanisms of the disorder using multiple model systems.

AbstractBackgroundPathogenic variants in AXIN2 have been associated with tooth agenesis, colon polyps, and colon cancer. Given the rare nature of this phenotype, we set out to collect additional genotypic and phenotypic information.MethodsData were collected via a structured questionnaire. Sequencing was performed in these patients mostly due to diagnostic purpose. A little more than half of the AXIN2 variant carriers were identified by NGS; other six were family members.ResultsHere, we report 13 individuals with a heterozygous AXIN2 pathogenic/likely pathogenic variant who have a variable expression of oligodontia‐colorectal cancer syndrome (OMIM 608615) or oligodontia‐cancer predisposition syndrome (ORPHA 300576). Three individuals from one family also had cleft palate, which might represent a new clinical feature of AXIN2 phenotype, also given the fact that AXIN2 polymorphisms have been found in association with oral clefting in population studies. AXIN2 has already been added to multigene cancer panel tests; further research should be conducted to determine whether it should be added to cleft lip/palate multigene panels.ConclusionMore clarity about oligodontia‐colorectal cancer syndrome, about the variable expression, and associated cancer risks is needed to improve clinical management and to establish guidelines for surveillance. We collected information about the surveillance that was advised, which might support clinical management of these patients.

AbstractAdvances have dated the genetic testing initially offered to evaluate for hereditary breast and ovarian cancer risks. Previous research has demonstrated that many patients have not updated testing. This study reviewed the incidence of additional analysis after an uninformative BRCA1/2 result and offered updated testing with limited barriers to those who had not completed. After viewing an educational video and providing informed consent, eligible patients were mailed a saliva collection kit to complete an 84‐gene hereditary cancer panel at no personal cost. A total of 704 patients had completed BRCA1/2 only testing between 2001 and 2020. Fifteen percent (N = 102) of the 671 patients with an uninformative BRCA1/2 result had already completed expanded testing. Most, 74 of 102 (73%), had been rereferred to medical genetics during a clinical visit related to cancer care. Those who had already completed additional testing were more likely to have a personal history of cancer (92% vs. 79%, p = 0.002) and live locally (p = 0.032). Invitation to complete updated testing through this study was sent to 372 people, and 116 (31%) consented to participate. For 142 of the 256 who did not proceed with testing through the study, proof of receipt of research information was available. In total, 22 pathogenic variants were reported in 21 of the 226 patients with updated testing from before and including our study: ATM (4), CHEK2 (4), LZTR1 (1), MUTYH (3), NBN (1), NF1 (1), NTHL1 (1), PALB2 (4), PMS2 (1), RAD50 (1), and SPINK1 (1). Many potential barriers of retesting were eliminated by removing personal costs or travel requirements. Still, only about 30% of patients agreed to participate, and a significant portion elected not to proceed. Future research could focus on the discovery of other factors that dissuade patients and what measures may better inform them on potential benefits.

AbstractBackgroundAchalasia‐addisonianism‐alacrima syndrome, frequently referred to as Allgrove syndrome or Triple A syndrome, is a multisystem disorder resulting from homozygous or compound heterozygous pathogenic variants in the gene encoding aladin (AAAS). Aladin is a member of the WD‐repeat family of proteins and is a component of the nuclear pore complex. It is thought to be involved in nuclear import and export of molecules. Here, we describe an individual with a paternally inherited truncating variant and a maternally inherited, novel missense variant in AAAS presenting with alacrima, achalasia, anejaculation, optic atrophy, muscle weakness, dysarthria, and autonomic dysfunction.MethodsWhole‐exome sequencing was performed in the proband, sister, and parents. Variants were confirmed by Sanger sequencing. The localization of aladin to the nuclear pore was assessed in cells expressing the patient variant.ResultsFunctional testing of the maternally inherited variant, p.(Arg270Pro), demonstrated decreased localization of aladin to the nuclear pore in cells expressing the variant, indicating a deleterious effect. Follow‐up testing in the proband's affected sister revealed that she also inherited the biallelic AAAS variants.ConclusionsReview of the patient's clinical, pathological, and genetic findings resulted in a diagnosis of Triple A syndrome.

Introduction: Family health history can be a valuable indicator of risk to develop certain cancers. Unfortunately, patient self-reported family history often contains inaccuracies, which might change recommendations for cancer screening. We endeavored to understand the difference between a patient’s self-reported family history and their electronic medical record (EMR) family history. One aim of this study was to determine if family history information contained in the EMR differs from patient-reported family history collected using a focused questionnaire. Methods: We created the Hereditary Cancer Questionnaire (HCQ) based on current guidelines and distributed to 314 patients in the Department of Family Medicine waiting room June 20 to August 1, 2018. The survey queried patients about specific cancers within their biological family to assess their risk of an inherited cancer syndrome. We used the questionnaire responses as a baseline when comparing family histories in the medical record. Results: Agreement between the EMR and the questionnaire data decreased as the patients’ risk for familial cancer increased. Meaning that the more significant a patient’s family cancer history, the less likely it was to be recorded accurately and consistently in the EMR. Patients with low-risk levels, or fewer instances of cancer in the family, had more consistencies between the EMR and the questionnaire. Conclusions: Given that physicians often make recommendations on incomplete information that is in the EMR, patients might not receive individualized preventive care based on a more complete family cancer history. This is especially true for individuals with more complicated and significant family history of cancer. An improved method of collecting family history, including increasing patient engagement, may help to decrease this disparity.

We describe the phenotype of a patient with extensive aortic, carotid, and abdominal dissections. The proband was found to have a heterozygous deletion of exons 21–34 inMYLK, which is a rare finding, as deletions in this gene have been infrequently reported. We describe this finding following detection in a proband with an extensive history of aortic, carotid, and abdominal dissections. Neoteric molecular modeling techniques to help determine the impact of this deletion on protein function indicated loss of function due to lack of any kinase domain. We also provide the electrostatics calculations from the wild type and mutant variant. Through a combined multiomic approach of clinical, functional, and protein informatics, we arrive at a data fusion for determination of pathogenicity embedded within the genetic code for this particular genetic variant, which, as a platform, continues to broaden its scope across the field of variants of uncertain significance classification.

Background. The ATP-binding cassette, subfamily D, member 1 (ABCD1) protein is a peroxisomal half-transporter that allows for very long chain fatty acid (VLCFA) degradation. Pathogenic variants of ABCD1 cause VLCFAs to build up in various tissues and bodily fluids, resulting in a disorder called X-linked adrenoleukodystrophy (X-ALD). This disorder is most commonly marked by adrenocortical insufficiency and high VLCFA concentration, and has varying levels of neurological involvement depending on phenotype. For example, the Addison-only form of X-ALD has no neurological impact, while the cerebral form of X-ALD often causes severe sensory loss, motor function impairment, cognitive decline, and death. Methods. A newly characterized and suspected pathogenic variant in ABCD1 was analyzed using our protein informatics platform (PIP). Personalized protein-level molecular studies were completed on genetic testing data, complementing the analysis and clinical study. Results. A case of adult onset adrenomyeloneuropathy (AMN) and a novel ABCD1 variant are presented. The unique ABCD1 protein is discussed, and the proband’s case is compared to existing reports of AMN. Conclusions. Data fusion from multiple sources was combined in a comprehensive approach yielding an enriched assessment of the patient’s disease and prognosis. Molecular modeling was performed on the variant to better characterize its clinical significance and confirm pathogenicity.

AbstractDiffuse idiopathic skeletal hyperostosis (DISH) is a disorder principally characterized by calcification and ossification of spinal ligaments and entheses. Fibrodysplasia ossificans progressiva (FOP) is a rare autosomal dominant disabling disorder characterized by progressive ossification of skeletal muscle, fascia, tendons, and ligaments. These conditions manifest phenotypic overlap in the ossification of tendons and ligaments. We describe herein a patient with DISH, exhibiting heterotopic ossification of the posterior longitudinal ligament where clinical whole exome sequencing identified a variant within ACVR1, a gene implicated in FOP. This variant, p.K400E, is a novel variant, not identified previously, and occurs in a highly conserved region across orthologs. We used sequence‐based predicative algorithms, molecular modeling, and molecular dynamics simulations, to test the potential for p.K400E to alter the structure and dynamics of ACVR1. We applied the same modeling and simulation methods to established FOP variants, to identify the detailed effects that they have on the ACVR1 protein, as well as to act as positive controls against which the effects of p.K400E could be evaluated. Our in silico molecular analyses support p.K400E as altering the behavior of ACVR1. In addition, functional testing to measure the effect of this variant on BMP‐pSMAD 1/5/8 target genes was carried out which revealed this variant to cause increased ID1 and Msx2 expression compared with the wild‐type receptor. This analysis supports the potential for the variant of uncertain significance to contribute to the patient's phenotype.