Status
Conditions
About
This study may identify genes that predict the seriousness of neurofibromatosis type 1 (NF1). Finding these genes may explain why some people with NF1 have more medical problems than others. The study will also examine medical problems in NF1 that are rarely seen and are not well understood.
Male and female patients with NF1 who have gone through puberty may be eligible for this study, as well as patients of any age who have unique or under-recognized disease features. Affected and unaffected family members, including parents, siblings, and more distant relatives, may also be enrolled. Candidates are screened with a discussion of medical history or review of medical records, or both. Participants undergo the following procedures:
Patients with NF1
Patients with NF1 who have unique or under-recognized disease features
Unaffected family members
Families are asked to give permission for researchers to recontact them for follow-up information, additional blood samples, or follow-up visit.
...
Full description
We hypothesize that normal germline variation in gene expression accounts, in part, for variation in the clinical severity and phenotype of the monogenic disorder neurofibromatosis type 1 (NF1). The phenotype of NF1 is constituted by a variety of quantifiable features; we term these features sub-phenotypes . Our main focus is on sub-phenotypes with published evidence of variation in expression from an inherited component. These include our primary sub-phenotype of spinal neurofibroma burden (quantified by MRI of spinal neurofibromas) and the secondary sub-phenotypes of dermal neurofibroma burden, head circumference, number of Lisch nodules, scoliosis, history of plexiform neurofibromas, and height. Other sub-phenotypes, as collected by a routine history and physical, will also be evaluated.
According to our hypothesis, the severity of a sub-phenotype will correlate with heritable differences in the germline expression of certain genes. As an example, consider a spectrum of individuals affected with the primary sub-phenotype of spinal neurofibroma burden. For most genes, there will be no relationship of expression level to the number of spinal neurofibromas. However, some genes will have a direct (or inverse, or other) correlation of their level of expression and the number of neurofibromas. Such genes would be considered as candidate modifier genes. The secondary sub-phenotypes will also be analyzed in a similar way. To limit false positives, candidate genes will then be tested for association (using the transmission/disequilibrium test, TDT) with the appropriate sub-phenotype.
Recruitment will be focused on identifying individuals with a range of severity of the primary sub-phenotype, spinal neurofibroma burden. We will primarily recruit post-pubertal individuals who meet the 1988 NIH criteria for neurofibromatosis type 1 (NIH Consensus Development Conference 1988). We will exclude those with recognized segmental or mosaic NF1. The rate of cutaneous neurofibroma growth and number is known to vary widely; these tumors typically appear in adolescence. For this reason we will ascertain patients after puberty. We expect most individuals to be 18 years or older, but will also accept post-pubertal pediatric patients (and use a hand film to demonstrate bone age). Parents (whether affected or not) are critical when using family-based tests of association (like the TDT) and tests of linkage and will also be recruited.
Tests of association with the TDT require trios (mother, father, proband). Multiple trios can be derived from a single family, if there are multiple affected individuals within the family. We set a recruitment goal of 100 trios and a ceiling of 1500 individuals (500 affected individuals, plus 1000 parents or additional sibs in about 400 families).
In the interest of improving care for people living with NF1, this protocol also seeks to characterize, at the PI s discretion, individuals with unique or under-recognized features of NF1 as well as individuals with NF1-like phenotypes, including those patients with a known or suspected RAS pathway disorder.
Enrollment
Sex
Ages
Volunteers
Inclusion and exclusion criteria
Group A: All affected individuals in a family who are post-pubertal male and female individuals and who meet the 1988 NIH criteria for neurofibromatosis type 1 (NIH Consensus Development Conference 1988).
Group B: Unaffected individuals greater than 2 years of age who are relatives of participants (especially parents, but also siblings) are eligible to enroll and are critical to the success of the study. These individuals may be of any gender and ethnicity. If the individual is pre-pubertal, s/he must have a brief evaluation at the NIH Clinical Center (abbreviated medical history and skin and eye exam) to ensure s/he is not affected with NF1.
Group C: individuals with unique or under-recognized features of NF1 of any age, gender or ethnicity and must have a correct clinical diagnosis of NF1 (NIH Consensus Development Conference 1988). all Group C participants enrolling in the study identify a physician who will be responsible for follow-up care so this can be arranged (if needed) at the conclusion of the evaluation at NIH.
For healthy normal volunteers used for MRI imaging of the spine, we will aim to recruit one male and one female from each of 5 decades (18-30 years, 31-40 years, 41-50 years, 51-60 years, 61-70 years). These individuals may be of any ethnicity.
Additional requirements include:
EXCLUSION CRITERIA:
EXCLUSION CRITERIA FOR GROUP A INDIVIDUALS INCLUDE:
EXCLUSION CRITERIA FOR GROUP B INDIVIDUALS INCLUDE:
1) A non-affected pregnant or lactating woman in a family for whom LCL immortalization will not be performed may participate. However, if she is a member of a multi-affected family (and thus her blood will be used to prepare LCLs) we will request that she donate a blood sample at the conclusion of her pregnancy or upon the weaning of her child.
EXCLUSION CRITERIA FOR GROUP C INDIVIDUALS INCLUDE:
1) Less than 2 years of age.
EXCLUSION CRITERIA FOR HEALTHY, NORMAL VOLUNTEERS INCLUDE:
313 participants in 2 patient groups
Loading...
Data sourced from clinicaltrials.gov
Clinical trials
Research sites
Resources
Legal