Mutations in the lamin B1 gene are not present in multiple sclerosis

Department of Genetics, Biology and Biochemistry, University of Torino, and S.C.D.U. Medical Genetics, A.O.U. San Giovanni Battista, Torino, Italy.
European Journal of Neurology (Impact Factor: 4.06). 05/2009; 16(4):544-6. DOI: 10.1111/j.1468-1331.2009.02536.x
Source: PubMed


Whole gene duplication of the lamin B1 gene (LMNB1), encoding for a protein of the nuclear lamina, causes an adult-onset autosomal dominant leukodystrophy (ADLD). Clinical features of ADLD (onset in adult life, dysautonomic symptoms, followed by pyramidal and cerebellar dysfunctions) partially resemble those of multiple sclerosis (MS), particularly the primary-progressive form. Our aim was to test whether LMNB1 gene mutations were present amongst patients with a diagnosis of MS.
One hundred eighty-two MS patients were screened for copy number variations of the LMNB1 gene using a qPCR assay. Point mutations in the LMNB1 gene were searched by denaturing high-performance liquid chromatography and direct sequencing in a subgroup of 16 patients with familial MS.
No duplication/deletion of the lamin B1 gene was found amongst MS patients, and no point mutation was identified in the familial cases.
Our work indicates that lamin B1 defects are probably not responsible for signs and symptoms resembling multiple sclerosis.

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