Gene for identifying individuals with familial dysautonomia
1-35. -35. (canceled)
This invention relates to methods and compositions useful for detecting mutations which cause Familial Dysautonomia. Familial dysautonomia (FD; Riley-Day syndrome), an Ashkenazi Jewish disorder, is the best known and most frequent of a group of congenital sensory neuropathies and is characterized by widespread sensory and variable autonomic dysfunction. Previously, we mapped the FD gene, DYS, to a 0.5 cM region of chromosome 9q31 and showed that the ethnic bias is due to a founder effect, with >99.5% of disease alleles sharing a common ancestral haplotype. To investigate the molecular basis of FD, we sequenced the minimal candidate region and cloned and characterized its 5 genes. One of these, IKBKAP, harbors two mutations that can cause FD. The major haplotype mutation is located in the donor splice site of intron 20. This mutation can result in skipping of exon 20 in the mRNA from FD patients, although they continue to express varying levels of wild-type message in a tissue-specific manner. RNA isolated from patient lymphoblasts is primarily wild-type, whereas only the deleted message is seen in RNA isolated from brain. The mutation associated with the minor haplotype in four patients is a missense (R696P) mutation in exon 19 that is predicted to disrupt a potential phosphorylation site. Our findings indicate that almost all cases of FD are caused by an unusual splice defect that displays tissue-specific expression; and they also provide the basis for rapid carrier screening in the Ashkenazi Jewish population.
1-35. -35. (canceled)
36. A method of detecting a FD mutation in a sample, comprising isolation of RNA from a tissue sample, amplifying the RNA using primers in exons 19 and 23;
- determining whether said sample contains a mutant product or a wild-type product, wherein the identification of a mutant product indicates the presence of an FD mutation in said sample.
- View Dependent Claims (37)
38-43. -43. (canceled)
44. A method for assaying for the presence of a mutation associated with Familial Dysautonomia in an individual comprising:
(a) providing a biological sample comprising DNA or RNA from the individual; and
(b) detecting the presence of FD1 or FD2 in the DNA, RNA, or cDNA made therefrom.
- View Dependent Claims (45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61)
- 62. A method for assaying for the presence of a mutation associated with Familial Dysautonomia in an individual comprising detecting a deletion of exon 20 in IKAP cDNA made from RNA isolated from the individual, wherein said exon is nucleotides 2,441-2,514 of SEQ ID NO: