Catherine Bove

A novel moesin-, ezrin-, radixin-like gene is a candidate for the neurofibromatosis 2 tumor suppressor

Neurofibromatosis 2 (NF2) is a dominantly inherited disorder characterized by the occurrence of bilateral vestibular schwannomas and other central nervous system tumors including multiple meningiomas. Genetic linkage studies and investigations of both sporadic and familial tumors suggest that NF2 is caused by inactivation of a tumor suppressor gene in chromosome 22q12. We have identified a candidate gene for the NF2 tumor suppressor that has suffered nonoverlapping deletions in DNA from two independent NF2 families and alterations in meningiomas from two unrelated NF2 patients. The candidate gene encodes a 587 amino acid protein with striking similarity to several members of a family of proteins proposed to link cytoskeletal components with proteins in the cell membrane. The NF2 gene may therefore constitute a novel class of tumor suppressor gene.

Mapping of the Mucolipidosis Type IV Gene to Chromosome 19p and Definition of Founder Haplotypes

Mucolipidosis type IV (MLIV) is a lysosomal storage disorder characterized by severe neurologic and ophthalmologic abnormalities. It is a rare autosomal recessive disease, and the majority of patients diagnosed, to date, are of Ashkenazi Jewish descent. We have mapped the MLIV gene to chromosome 19p13.2-13.3 by linkage analysis with 15 markers in 13 families. A maximum LOD score of 5.51 with no recombinants was observed with marker D19S873. Several markers in the linked interval also displayed significant linkage disequilibrium with the disorder. We constructed haplotypes in 26 Ashkenazi Jewish families and demonstrate the existence of two founder chromosomes in this population. The localization of MLIV to chromosome 19 will permit genetic prenatal diagnosis in affected families and will aid in the isolation of the disease gene.

Quality of life assessment in adults with type 1 Gaucher disease

The effect of enzyme replacement therapy on health-related quality of life in 25 adults with type 1 Gaucher disease was investigated over a 2-year period. Quality of life was assessed using the SF-36 Health Survey (SF-36). Psychological functioning was assessed using the Symptom Checklist-90R. The results indicated significant improvement in 7 of 8 SF scale scores beginning at 18 months of therapy (P<0.05 to 0.001). The SF scale showing improvement first was Vitality (energy level and fatigue) at 6 months of therapy (P<0.01). The SF-36 scales showing the largest improvements were Role-Physical and Social Functioning (P<0.001). Compared to the general US adult population, the study populations health profile was significantly lower prior to starting therapy but by 24 months of therapy there were no differences between the two. No differences were found in psychological functioning compared to a US adult normative group at the start of therapy. However, within the study population there was significant improvement in mood and global functioning and fewer psychological symptoms reported at 24 months of therapy. The findings indicate that enzyme replacement therapy for type 1 Gaucher disease has a positive impact on health-related quality of life from the patients perspective.

Spinal ependymomas in neurofibromatosis Type 2: a retrospective analysis of 55 patients

OBJECT The aim of this paper was to define the clinical characteristics of spinal ependymomas associated with neurofibromatosis Type 2 (NF2). METHODS The authors retrospectively reviewed the clinical records of patients with NF2 who had imaging findings consistent with ependymomas and were seen at Massachusetts General Hospital between 1994 and 2007. Clinical characteristics of these patients were obtained from hospital records, imaging studies, surgical reports, and pathology reports. Mutational analysis of the NF2 gene was performed in 37 of 44 unrelated patients. RESULTS Fifty-five patients met inclusion criteria for the study. The median age at diagnosis of NF2 was 21 years; the median time after diagnosis until identification of ependymomas was 5 years. Multiple ependymomas were present in 58% of patients. The most common site of involvement was the cervical cord or cervicomedullary junction (86% of imaging studies), followed by the thoracic and lumbar cords (62% and 8%, respectively). The majority of patients had no symptoms related to their tumors (42 patients [76%]). After a median follow-up of 50 months, surgery was performed in 11 patients (20%) for symptomatic progression (indications for surgery). Mutational analysis of the NF2 gene detected alterations in 28 (76%) of 37 unrelated patients, with nonsense and frameshift mutations accounting for 64% of detected mutations. The high rate of truncating mutations may help explain the high tumor burden in these patients. CONCLUSIONS Neurofibromatosis Type 2-related ependymomas exhibit an indolent growth pattern with tumor progression limited to a minority of patients. The authors believe that surveillance is reasonable for asymptomatic ependymomas, including those with cystic areas that expand the cord. For symptomatic tumors, resection may be warranted depending on age, overall clinical status, and ease of resectability.

Presymptomatic and predisposition genetic testing: Ethical and social considerations

OBJECTIVE To provide an overview of the ethical and social concerns that are raised by the use of new genetic tests in asymptomatic persons. DATA SOURCES Review articles, research studies and legislation related to genetic testing. CONCLUSIONS Predisposition and presymptomatic testing is possible to any age for adult onset disorders if a mutation is known. Testing without early effective interventions is controversial, especially prenatally and in children. Issues of privacy, discrimination, stigmatization and emotional stress are potential problems. Informed consent is essential before deciding to test. Awareness of the implications of testing can enhance the nurses advocacy role. IMPLICATIONS FOR NURSING PRACTICE More studies are necessary to identify the impact of presymptomatic testing on adults and children. Nursing research to identify the family concerns, and to develop effective educational, counseling, and supportive interventions would make a valuable contribution.

A questionnaire study for 128 patients with Gaucher disease.

Gaucher disease is an uncommon autosomal recessive disorder characterized by lysosomal storage of glucosyl ceramide, a material released during cell degradation. Patients with Gaucher disease often have significant hematologic, bone structural, and visceral problems which sometimes greatly affect their health and life style. Based on some extraordinary scientific discoveries over the past 45 years, a treatment system has evolved which consists of administration of an enzyme, which destroys the lysosome‐stored material and to some extent restores the patients to good health. There are still some problems for these patients; however, and the purpose of the study is to define some of the clinical, sociologic, and psychologic problems with a specially designed questionnaire. Questionnaire data was collected for 128 patients from two institutions with complete anonymity, and the information compared against data from a National Health Inteview Survey. The results show that many of the patients still have fairly extensive problems, which could possibly be helped by some alterations in treatment protocols.

Presymptomatic Genetic Testing in Children for Neurofibromatosis 2

Genetic testing in children, when there is a question of whether or not there is a clear medical benefit that will accrue to the child, is a controversial topic within the health care community. A convenience sample of 10 parents from nine families who had made the decision whether or not to test their children for the neurofibromatosis 2 gene mutation was asked in interviews to describe why they made their choice about presymptomatic testing for this late-onset disease. Findings from a narrative analysis revealed how the nine parents who tested or intended to test their young children saw the decision as a pathway to knowledge that would help the family unit. All parents interviewed noted that their decision was informed by their health team and was not difficult to make. Implications of these findings for bioethical analysis are presented.

FACTORS PERCEIVED TO INFLUENCE PARENTAL DECISION-MAKING REGARDING PRESYMPTOMATIC TESTING OF CHILDREN AT RISK FOR TREATABLE ADULT-ONSET GENETIC DISORDERS

The purpose of this study was to identify those critical factors that genetic nurse experts perceived could influence parental decision-making to seek or to reject presymptomatic testing of their children at risk for treatable adult-onset genetic disorders (neurofibromatosis 2, familial adenomatous polyposis, and von Hippel Lindeau disorder). Perceptions of ISONG genetic nurse specialists were surveyed through a modified Delphi technique and four major themes emerged: personal experience with severity of genetic disorder, receiving accurate information from credible sources, availability of quality treatment, and risk perception. Currently, there is a paucity of extant research that identifies critical factors influencing parental decision-making about this relatively new testing alternative for children. Thus, these experts are an important source of valuable information needed to identify such factors. Findings may be useful to design a qualitative study with parents to investigate this issue.