Expanding the genetic and phenotypic landscape of replication factor C complex-related disorders: RFC4 deficiency is linked to a multisystemic disorder.

The precise regulation of DNA replication is vital for cellular division and genomic integrity. Central to this process is the replication factor C (RFC) complex, encompassing five subunits, which loads proliferating cell nuclear antigen onto DNA to facilitate the recruitment of replication and repair proteins and enhance DNA polymerase processivity. While RFC1's role in cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) is known, the contributions of RFC2-5 subunits on human Mendelian disorders is largely unexplored. Our research links bi-allelic variants in RFC4, encoding a core RFC complex subunit, to an undiagnosed disorder characterized by incoordination and muscle weakness, hearing impairment, and decreased body weight. We discovered across nine affected individuals rare, conserved, predicted pathogenic variants in RFC4, all likely to disrupt the C-terminal domain indispensable for RFC complex formation. Analysis of a previously determined cryo-EM structure of RFC bound to proliferating cell nuclear antigen suggested that the variants disrupt interactions within RFC4 and/or destabilize the RFC complex. Cellular studies using RFC4-deficient HeLa cells and primary fibroblasts demonstrated decreased RFC4 protein, compromised stability of the other RFC complex subunits, and perturbed RFC complex formation. Additionally, functional studies of the RFC4 variants affirmed diminished RFC complex formation, and cell cycle studies suggested perturbation of DNA replication and cell cycle progression. Our integrated approach of combining in silico, structural, cellular, and functional analyses establishes compelling evidence that bi-allelic loss-of-function RFC4 variants contribute to the pathogenesis of this multisystemic disorder. These insights broaden our understanding of the RFC complex and its role in human health and disease.

Time tracking and comparison of genetic counseling tasks in inpatient and outpatient settings.

Genetic counselors (GCs) practice in critical care settings. Some GCs have full-time inpatient roles, while most GCs who see inpatients do so as needed or on a rotating schedule in addition to seeing patients in an outpatient setting. Few studies have tracked and compared the amount of time it takes GCs to perform tasks in the inpatient and outpatient settings. Genetic counselors were invited to participate in this study via the National Society of Genetic Counselors research listserv. Participants completed an online survey asking how their role is structured and what types of support are available to them while seeing inpatients. They also performed time tracking for 16 tasks known to be associated with inpatient and/or outpatient care via RedCap. These tasks include direct patient care, care coordination, and other tasks which encapsulate a new patient encounter from beginning to end. Forty-two inpatient encounters and 26 outpatient encounters were analyzed. The total average time spent on an inpatient consult (3 h and 38.5 min) was significantly higher than the time spent on an outpatient consult (2 h and 24.7 min; p < 0.05). Individually, genetic counselors spent significantly more time on the following tasks in an inpatient setting: direct follow-up encounters, multidisciplinary team communication, results disclosure encounters, results disclosure documentation, traveling, and waiting. Follow-up encounters, traveling, and waiting happen almost exclusively in inpatient settings. Short answer prompts regarding structure of GC role and available support revealed themes including lack of inpatient role structure, challenges with balancing between inpatient and outpatient tasks, and varied institutional support. These results promote further discussion about how to support GCs who see inpatients as these roles expand. Some suggestions include increased FTE/protected time and/or GCA support specific to the inpatient role.

Genetic counseling in diabetes mellitus: A practice resource of the National Society of Genetic Counselors.

Diabetes mellitus is a group of diseases characterized by hyperglycemia and its consequences, affecting over 34 million individuals in the United States and 422 million worldwide. While most diabetes is polygenic and is classified as type 1 (T1D), type 2 (T2D), or gestational diabetes (GDM), at least 0.4% of all diabetes is monogenic in nature. Correct diagnosis of monogenic diabetes has important implications for glycemic management and genetic counseling. We provide this Practice Resource to familiarize the genetic counseling community with (1) the existence of monogenic diabetes, (2) how it differs from more common polygenic/complex diabetes types, (3) the advantage of a correct diagnosis, and (4) guidance for identifying, counseling, and testing patients and families with suspected monogenic diabetes. This document is intended for genetic counselors and other healthcare professionals providing clinical services in any setting, with the goal of maximizing the likelihood of a correct diagnosis of monogenic diabetes and access to related care.

Establishing a mentorship program for prospective genetic counseling graduate students: Two cycles of program experience.

Mentorship has been a long-standing and important piece of healthcare training, but few formal, structured mentorship programs exist in the genetic counseling field. Our report describes the creation and evaluation of the Genetic Counseling Assistant Mentorship Program (GCAMP) after two cycles of the program. Genetic counseling assistant (GCA) mentees were paired with genetic counselor mentors for support and advice primarily surrounding graduate school applications and professional development. Pairs were encouraged to meet at regular intervals, but the specific meeting patterns were determined by the pair based on the needs of the mentee. The GCAMP also involved electronic and interactive resources for mentees, which were continually developed. Many of the electronic resources were created and maintained by past and current GCAs, such as a list of local shadowing and advocacy opportunities and a list of factors to consider when evaluating graduate programs. Interactive resources included workshops, mock graduate school interviews, reviews of graduate school application materials, and social events. Mentors were also provided with resources about mentorship. Surveys were conducted to evaluate the program. Overall satisfaction with the program and the mentoring relationship was high among both mentees and mentors. In aggregate, results revealed that mentees felt strongly supported by the mentorship program and were highly satisfied with their mentorship experience. Results also showed that mentors enjoyed a high level of fulfillment and professional development themselves by participating in the program.

A case study of atypical Larsen syndrome with absent hallmark joint dislocations.

BACKGROUND: A family with skeletal and craniofacial anomalies is presented. Whole-exome sequencing (WES) analysis indicated a diagnosis of Larsen syndrome, although their clinical presentation does not include the hallmark joint dislocations typically observed in Larsen syndrome. METHODS: Patient consent for the sharing of de-identified clinical and genetic information, along with use of photographs for publication, was obtained. WES and variant segregation analysis by WES were performed by commercial laboratory, GeneDx (Gaithersburg, MD), on peripheral blood samples from the proband, her brother, and her parents using methods detailed on their website for test XomeDx Whole Exome Sequencing Trio (https://www.genedx.com/test-catalog/available-tests/xomedx-whole-exome-sequencing-trio/). WES uses next-generation sequencing (NGS) technology to assess for variants within the coding regions, or exons, of approximately 23,000 genes. For the FLNB gene (NM_001457.3), 100% of the coding region was covered at a minimum of 10x. GeneDx uses Sanger sequencing to confirm NGS variants. RESULTS: WES revealed a heterozygous pathogenic variant, p.Glu227Lys (c.679G>A), in the FLNB gene in three out of the four family members tested. This variant is associated with Larsen syndrome, a skeletal dysplasia condition with a wide range of phenotypic variability that usually includes congenital joint dislocations. CONCLUSION: This is a highly unusual presentation of Larsen syndrome in which the identifying hallmark trait is absent in the patients' phenotypes.

Endosomal trafficking defects in patient cells with KIAA1109 biallelic variants.

The uncharacterized gene KIAA1 109 has recently been associated with a congenital neurological malformation disorder that variably presents with arthrogryposis, craniofacial and/or cardiac abnormalities. We have identified two additional patients with compound heterozygous KIAA1109 variants presenting with the same neurological malformations. The mechanism whereby KIAA1109 loss of function causes this spectrum of disorders was the primary focus of our studies. We hypothesized that KIAA1109 function could be conserved relative to the fly gene tweek and examined endocytosis and endosome recycling in patient fibroblasts. Furthermore, we examined the structure of the cytoskeleton and cilia based on functional overlap with endocytosis and several known etiologies for neuronal migration disorders. Utilizing primary dermal fibroblasts from one patient and a healthy donor, we performed immunofluorescence and endocytosis assays to examine the endosomal, cytoskeletal, and ciliary cellular phenotypes. We found notable abnormalities in endosomal trafficking and endosome recycling pathways. We also observed changes in the actin cytoskeleton and cilia structural dynamics. We conclude that the function of KIAA1109 in humans may indeed overlap with the function of the Drosophila ortholog, resulting in perturbations to endosomal trafficking and the actin cytoskeleton. These alterations have ripple effects, altering many pathways that are critical for proper neuronal migration and embryonic development.

Factors complicating the informed consent process for whole exome sequencing in neonatal and pediatic intensive care units.

Whole exome and whole genome sequencing (WES/WGS) is increasingly utilized in inpatient settings such as neonatal and pediatric intensive care units (ICU), but no research has explored the process of informed consent in this setting. My experience as an inpatient genetic counselor has illuminated factors unique to the ICU that may threaten elements of informed consent such as voluntariness, disclosure, understanding, and capacity. I present three cases that exemplify elements complicating consent counseling for WES/WGS in the ICU, including the emotional state of the parents, involvements of other healthcare providers, environmental distractions and competing clinical priorities. I offer strategies to navigate these factors based on my experience.

The importance of genetics and genetic counselors in the evaluation of patients with bicuspid aortic valve and aortopathy.

PURPOSE OF REVIEW: Bicuspid aortic valve (BAV) is a common congenital heart defect, with an estimated frequency of 1-2% in the general population. BAV may occur as an isolated finding or as a feature of certain syndromes. This article discusses potential genetic causes of BAV, includes a list of current known and candidate genes associated with BAV, provides a hypothetical case demonstrating the importance of genetic testing and cascade screening, and highlights the value of genetic counselors specializing in cardiovascular genetics. RECENT FINDINGS: Individuals with BAV are at significantly increased risk of progressive aortic valve disease and aortic root aneurysms. There is high heritability associated with BAV, and several specific genes have recently been associated with BAV. There is wide phenotypic variability among BAV malformations, including which cusps are involved and the degree of aortic root involvement. Genotype-phenotype correlations exist that impact treatment recommendations. Genetic testing can reduce morbidity and mortality by guiding management strategies and identifying asymptomatic relatives before significant complications occur. SUMMARY: Identifying cases of BAV with an identifiable genetic cause can significantly impact patients and family members. The list of associated genes is constantly growing. Genetic counselors have an important role in the evaluation of families at risk of BAV.

Physicians' Awareness and Utilization of Genetic Services in Texas.

The number of disorders for which genetic testing is available has increased nearly 500% in the past 15 years. Access to genetic tests and services often hinges on physicians' ability to identify patients at risk for genetic disease and provide appropriate testing and counseling or refer to genetic specialists. Recent research demonstrates the need for referrals to genetic specialists by showing that many physicians lack skills required to perform appropriate genetic services, such as making proper risk assessments, providing genetic counseling, ordering genetic testing and interpreting results. However, little research exists on physicians' awareness and utilization of genetic services. In this study, an electronic survey evaluating practicing physicians' awareness of, utilization of and perceived barriers to genetic services in Texas, and interest in learning more about genetics and genetic services was distributed via state physician organizations. Of the 157 participants, approximately half reported they were moderately or very aware of genetic testing and services in their area. Very few reported awareness of telemedicine services. Over two-thirds reported never or rarely referring to genetic counselors or other genetic specialists, despite 75% reporting they had noticed an increased impact of genetics on their field and 61% reporting they had discussed genetics more in their day-to-day practice in the last 5-10 years. Only 20% reported genetics was very integral to their specialty. Over three-fourths of all participants indicated interest in learning more about genetics, genetic testing, and genetic services. Among the most frequently chosen barriers to genetic counselors were awareness-related barriers such as not knowing how to refer to a genetic counselor. Responses to many items varied significantly by medical specialty. The results identify a need to increase awareness of genetic services and referral logistics. Specific findings can help direct outreach efforts to educate clinicians, such as developing clinically meaningful, specialty-specific educational objectives.