The age of human mutation: genealogical and linkage disequilibrium analysis of the CLN5 mutation in the Finnish population.

Variant late infantile neuronal ceroid lipofuscinosis (vLINCL) is an autosomal recessive progressive encephalopathy of childhood enriched in the western part of Finland, with a local incidence of 1 in 1500. We recently assigned the locus for vLINCL, CLN5, to 13q21.1-q32. In the present study, the haplotype analysis of Finnish CLN5 chromosomes provides evidence that one single mutation causes vLINCL in the Finnish population. Eight microsatellite markers closely linked to the CLN5 gene on chromosome 13q were analyzed, to study identity by descent by shared haplotype analysis. One single haplotype formed by flanking markers D13S160 and D13S162 in strong linkage disequilibrium (P < .0001) was present in 81% of disease-bearing chromosomes. Allele 4 at the marker locus D13S162 was detected in 94% of disease-bearing chromosomes. To evaluate the age of the CLN5 mutation by virtue of its restricted geographical distribution, church records were used to identify the common ancestors for 18 vLINCL families diagnosed in Finland. The pedigrees of the vLINCL ancestors merged on many occasions, which also supports a single founder mutation that obviously happened 20 to 30 generations ago (i.e., approximately 500 years ago) in this isolated population. Linkage disequilibrium was detected with seven markers covering an extended genetic distance of 11 cM, which further supports the young age of the CLN5 mutation. When the results of genealogical and linkage disequilibrium studies were combined, the CLN5 gene was predicted to lie approximately 200 - 400 kb (total range 30 - 1360 kb) from the closest marker D13S162.

[1]  J. Kere,et al.  Fine mapping of the congenital chloride diarrhea gene by linkage disequilibrium. , 1995, American journal of human genetics.

[2]  L. Peltonen,et al.  Random search for shared chromosomal regions in four affected individuals: the assignment of a new hereditary ataxia locus. , 1995, American journal of human genetics.

[3]  I. Järvelä,et al.  Batten disease gene, CLN3: linkage disequilibrium mapping in the Finnish population, and analysis of European haplotypes. , 1995, American journal of human genetics.

[4]  J. Terwilliger A powerful likelihood method for the analysis of linkage disequilibrium between trait loci and one or more polymorphic marker loci. , 1995, American journal of human genetics.

[5]  N. Risch,et al.  Genetic analysis of idiopathic torsion dystonia in Ashkenazi Jews and their recent descent from a small founder population , 1995, Nature Genetics.

[6]  L. Jorde Linkage disequilibrium as a gene-mapping tool. , 1995, American journal of human genetics.

[7]  L. Peltonen,et al.  Infantile Onset Spinocerebellar Ataxia Represents an Allelic Disease Distinct from Other Hereditary Ataxias , 1994, Pediatric Research.

[8]  L. Peltonen,et al.  Defined chromosomal assignment of CLN5 demonstrates that at least four genetic loci are involved in the pathogenesis of human ceroid lipofuscinoses. , 1994, American journal of human genetics.

[9]  Cécile Fizames,et al.  The 1993–94 Généthon human genetic linkage map , 1994, Nature Genetics.

[10]  X. Estivill,et al.  The origin of the major cystic fibrosis mutation (ΔF508) in European populations , 1994, Nature Genetics.

[11]  L. Peltonen,et al.  A variant form of late infantile neuronal ceroid lipofuscinosis (CLN5) is not an allelic form of Batten (Spielmeyer-Vogt-Sjögren, CLN3) disease: exclusion of linkage to the CLN3 region of chromosome 16. , 1994, Genomics.

[12]  P. Pontarotti,et al.  Anonymous marker loci within 400 kb of HLA-A generate haplotypes in linkage disequilibrium with the hemochromatosis gene (HFE) , 1994, American journal of human genetics.

[13]  R. Tanguay,et al.  Identification of a stop mutation in five Finnish patients suffering from hereditary tyrosinemia type I. , 1994, Human molecular genetics.

[14]  R. Richards,et al.  Familial Mediterranean fever (FMF) in Moroccan Jews: demonstration of a founder effect by extended haplotype analysis. , 1993, American journal of human genetics.

[15]  L. Peltonen,et al.  Refined assignment of the infantile neuronal ceroid lipofuscinosis (INCL, CLN1) locus at 1p32: incorporation of linkage disequilibrium in multipoint analysis. , 1993, Genomics.

[16]  Eric Lander,et al.  Linkage disequilibrium mapping in isolated founder populations: diastrophic dysplasia in Finland , 1992, Nature Genetics.

[17]  L. Peltonen,et al.  Spectrum of mutations in aspartylglucosaminuria. , 1991, Proceedings of the National Academy of Sciences of the United States of America.

[18]  I. Järvelä Infantile neuronal ceroid lipofuscinosis (CLN1): linkage disequilibrium in the Finnish population and evidence that variant late infantile form (variant CLN2) represents a nonallelic locus. , 1991, Genomics.

[19]  E. Sohar,et al.  Familial Mediterranean fever. , 1955, Klinische Padiatrie.

[20]  L. Tsui,et al.  Identification of the cystic fibrosis gene: genetic analysis. , 1989, Science.

[21]  K. Sainio,et al.  A Variant of Jansky-Bielschowsky Disease , 1982, Neuropediatrics.

[22]  J. Perheentupa,et al.  Hereditary diseases in Finland; rare flora in rare soul. , 1973, Annals of clinical research.