Christina Zaleski

Mutations in Transforming Growth Factor-β Receptor Type II Cause Familial Thoracic Aortic Aneurysms and Dissections

Background—A genetic predisposition for progressive enlargement of thoracic aortic aneurysms leading to type A dissection (TAAD) is inherited in an autosomal-dominant manner in up to 19% of patients, and a number of chromosomal loci have been identified for the condition. Having mapped a TAAD locus to 3p24–25, we sequenced the gene for transforming growth factor-&bgr; receptor type II (TGFBR2) to determine whether mutations in this gene resulted in familial TAAD. Methods and Results—We sequenced all 8 coding exons of TGFBR2 by using genomic DNA from 80 unrelated familial TAAD cases. We found TGFBR2 mutations in 4 unrelated families with familial TAAD who did not have Marfan syndrome. Affected family members also had descending aortic disease and aneurysms of other arteries. Strikingly, all 4 mutations affected an arginine residue at position 460 in the intracellular domain, suggesting a mutation “hot spot” for familial TAAD. Despite identical mutations in the families, assessment of linked polymorphisms suggested that these families were not distantly related. Structural analysis of the TGFBR2 serine/threonine kinase domain revealed that R460 is strategically located within a highly conserved region of this domain and that the amino acid substitutions resulting from these mutations will interfere with the receptor’s ability to transduce signals. Conclusion—Germline TGFBR2 mutations are responsible for the inherited predisposition to familial TAAD in 5% of these cases. Our results have broad implications for understanding the role of TGF-&bgr; signaling in the pathophysiology of TAAD.

Subtelomeric deletions of chromosome 9q: A novel microdeletion syndrome

Fluorescent in situ hybridization (FISH) screening of subtelomeric rearrangements has resulted in the identification of previously unrecognized chromosomal causes of mental retardation with and without dysmorphic features. This article reports the phenotypic and molecular breakpoint characterization in a cohort of 12 patients with subtelomeric deletions of chromosome 9q34. The phenotypic findings are consistent amongst these individuals and consist of mental retardation, distinct facial features and congenital heart defects (primarily conotruncal defects). Detailed breakpoint mapping by FISH, microsatellite and single nucleotide polymorphism (SNP) genotyping analysis has narrowed the commonly deleted region to an approximately 1.2 Mb interval containing 14 known transcripts. The majority of the proximal deletion breakpoints fall within a 400 kb interval between SNP markers C12020842 proximally and C80658 distally suggesting a common breakpoint in this interval.

Clinical genetics provider real-time workflow study

Purpose: Our work is the first documentation, in real time, of workflow in a general genetics department including data on patient care, research, and other activities for both clinical geneticists and genetic counselors.Methods: All physician geneticists and genetic counselors in the medical genetics department used an electronic tool to record their activities in 15 minute increments during clinic hours, evenings, and weekends over a 10-week period.Results: The average work week was 54.1 hours for physicians and 43.5 hours for genetic counselors. During clinic hours physicians spent about one-fourth of their time on direct patient care, one-fourth on other patient-related activities, one-fourth on research unrelated to individual patient care, and the remaining fourth on all other activities. However, after hours and on weekends they spent most of their time on research. Genetic counselors spent half of their time on patient-related activities, one-fourth on direct patient care, and the remainder on all other activities. The total professional time averaged 7 hours per new patient and 3.5 hours per follow-up with nearly 60% of this time devoted to patient-related activities.Conclusions: The labor intensive nature of clinical genetics, the large amount of time devoted to patient-related activities, and continuing limitations on billing by genetic counselors all contribute to the financial challenges faced by genetics departments.

Newborn Screening for Cystic Fibrosis: Parents’ Preferences Regarding Counseling At the Time of Infants’ Sweat Test

Newborn screening (NBS) protocols for cystic fibrosis (CF) are the first regional population-based programs to incorporate DNA analysis into their procedures. Research about these programs can inform policy and practice regarding how best to counsel families with abnormal NBS results. The grounded theory method guided interviews with 33 families whose infants had abnormal CF NBS results. A dimensional analysis of these interviews provided a theoretical framework describing parents’ preferences regarding counseling during their infants sweat test appointment. This framework describes the contexts and characteristics of the two main dimensions of parents’ preferences: factual information and emotional support. Factual information included learning about the probability of a CF diagnosis, CF disease facts, sweat test procedure, and CF genetics. Social support consisted of offering parents a choice about the timing and amount of CF information, showing empathy for their distress, instilling hope, personalizing counseling, and providing hospitality. This framework also explains the consequences of counseling that matched versus mismatched parental preferences in these domains. Counseling that matched parents preferences reduced parents’ distress while mismatched counseling tended to increase parents’ worry about their infant.

The co-occurrence of early onset Parkinson disease and 22q11.2 deletion syndrome.

The Co-Occurrence of Early Onset Parkinson Disease and 22q11.2 Deletion Syndrome Christina Zaleski, Anne S. Bassett, Karen Tam, Andrea L. Shugar, Eva W.C. Chow, and Elizabeth McPherson* Department of Medical Genetic Services, Marshfield Clinic, Marshfield, Wisconsin Clinical Genetics Research Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, Ontario, Canada

Wisconsin stillbirth services program: A multifocal approach to stillbirth analysis

Stillbirth accounts for about 26,000 deaths annually in the US. In most previous studies, discrete causes are identified in less than half of all stillbirths. In order to identify causes and non‐causal but potentially contributing abnormalities, we analyzed 416 of the most recent (2004–2010) Wisconsin Stillbirth Service Program (WiSSP) cases from a multifocal approach. In 70% of cases a cause sufficient to independently explain the demise was identified including 40% placental, 21.5% fetal, and 12.7% maternal. Results for stillbirths and second trimester miscarriages did not differ significantly. In 95% of cases at least one cause or non‐causal abnormality was recognizable, and in two‐thirds of cases, more than one cause or non‐causal abnormality was identified. In cases with maternal cause, the placenta was virtually always abnormal. Both placentas (59%) and fetuses (38%) were frequently smaller than expected for gestational age. Previous miscarriage and/or stillbirth were risk factors for second and third trimester losses, with 35% of previous pregnancies ending in fetal demise. Recommendations include complete evaluation of all second and third trimester losses with special attention to placental pathology and thorough investigation for multiple causes or abnormalities whether or not a primary cause is initially recognized. Improved understanding of the causes of late miscarriage and stillbirth may contribute to recognition and management of pregnancies at risk and eventually to prevention of stillbirth.

Molecular Testing for Cystic Fibrosis Carrier Status Practice Guidelines: Recommendations of the National Society of Genetic Counselors

PurposeTo provide practice recommendations for genetic counselors whose clients are considering cystic fibrosis (CF) carrier testing or seeking information regarding CF molecular test results. The goals of these recommendations are to: 1) Provide updated information about the natural history, diagnosis, and treatment of CF and related conditions. 2) Supplement genetic counselors’ knowledge and understanding of the available carrier screening and diagnostic testing options. 3) Describe the current state of genotype/phenotype correlations for CFTR mutations and an approach to interpreting both novel and previously described variants. 4) Provide a framework for genetic counselors to assist clients’ decision-making regarding CF carrier testing, prenatal diagnosis, and pregnancy management. Disclaimer The practice guidelines of the National Society of Genetic Counselors (NSGC) are developed by members of the NSGC to assist genetic counselors and other health care providers in making decisions about appropriate management of genetic concerns; including access to and/or delivery of services. Each practice guideline focuses on a clinical or practice-based issue, and is the result of a review and analysis of current professional literature believed to be reliable. As such, information and recommendations within the NSGC practice guidelines reflect the current scientific and clinical knowledge at the time of publication, are only current as of their publication date, and are subject to change without notice as advances emerge.In addition, variations in practice, which take into account the needs of the individual patient and the resources and limitations unique to the institution or type of practice, may warrant approaches, treatments and/or procedures that differ from the recommendations outlined in this guideline. Therefore, these recommendations should not be construed as dictating an exclusive course of management, nor does the use of such recommendations guarantee a particular outcome. Genetic counseling practice guidelines are never intended to displace a health care provider’s best medical judgment based on the clinical circumstances of a particular patient or patient population.Practice guidelines are published by NSGC for educational and informational purposes only, and NSGC does not “approve” or “endorse” any specific methods, practices, or sources of information.

A Tailored Approach to Family-Centered Genetic Counseling for Cystic Fibrosis Newborn Screening: The Wisconsin Model

This article describes the development of a tailored family-centered approach to genetic counseling following abnormal newborn screening (NBS) for cystic fibrosis (CF). A genetic counseling consortium reviewed research literature, selected theoretical frameworks, and incorporated counseling psychology micro skills. This innovative intervention integrated theories and empirically validated techniques. Pilot testing and parent feedback confirmed satisfaction with and feasibility of the approach designed to (a) minimize parents’ distress, (b) facilitate parents’ understanding, (c) increase parents’ capacities to use genetic information, and (d) enhance parents’ experiences with genetic counseling. Counselors engage in a highly interactive process of evaluating parents’ needs and tailoring assessments and interventions that include a therapeutic environment, the family’s emotional needs, parents’ informational needs, and a follow-up plan. This promising new model is the first to establish a theory-driven, evidence-based standard for genetic counseling in the context of NBS for CF. Additional research will evaluate the model’s efficacy in clinical practice.

Factors accounting for a missed diagnosis of cystic fibrosis after newborn screening

Newborn screening is a public health policy program involving the centralized testing laboratory, infant and their family, primary care provider, and subspecialist for confirmatory testing and follow‐up of abnormal results. Cystic fibrosis (CF) newborn screening has now been enacted in all 50 states and the District of Columbia and throughout many countries in the world. Although CF neonatal screening will identify the vast majority of infants with CF, there are many factors in the newborn screening system that can lead to a missed diagnosis of CF. To inform clinicians, this article summarizes the CF newborn screening system and highlights 14 factors that can account for a missed diagnosis of CF. Care providers should maintain a high suspicion for CF if there are compatible symptoms, regardless of the results of the newborn screening test. These factors in newborn screening programs leading to a missed diagnosis of CF present opportunities for quality improvement in specimen collection, laboratory analysis of immunoreactive tryspinogen (IRT) and CF mutation testing, communication, and sweat testing. Pediatr Pulmonol. 2011; 46: 1166–1174.

Patient and Family Experiences and Opinions on Adding 22q11 Deletion Syndrome to the Newborn Screen

Abstract22q11 deletion syndrome (22qDS) has recently been proposed for addition to the newborn screening panel in Wisconsin and it seems likely that it may soon be considered in other states as well. Input from patients with 22qDS and their family was gathered from 21 phone interviews. Cardiac, palate, hypocalcemia, and multiple anomalies were common reasons for involved patients to be diagnosed, though age at diagnosis ranged from birth to adulthood. Many commented on their struggles with 22qDS, including worries about the future and the patient’s independence. In general, respondents favored newborn screening for 22qDS because it would help prevent some medical problems, increase access to services, explain existing problems, and identify mild cases. However, a minority expressed reservations, including concerns that it would disrupt bonding, could be too costly, and would not be useful for mild cases.