| Part One. Phasic Studies on New Susceptible Gene Locus of MyotonicDystrophyBackground and objectiveMyotonic dystrophy (DM), the most common form of muscular dystrophy in adults, is characterized by affected multisystemic symptoms and has a high disabled rate. Up to now it is reported that two gene mutation loci caused DM, which were named DM1,and DM2 respectively. DM1 type is the abnormal expansion of trinucleotide tandem CTG in the 3' untranslated region of the dystrophia myotonica-protein kinase(DMPK) gene located in chromosome 3q21.Some domestic and foreign studies suggested that there should be a new susceptible gene locus caused DM. This study is to make clear possible existence of a new susceptible gene locus in DM and approach its possible location in virtue of a big DM family. MethodsDetermined 31 members from a DM family in shanghai, China as objects, we collected their blood samples, disposed of these samples with following methods by turns, which were on the basis of partial work previously: Damplified the gene segment by PCR and carried Southern blotting to test the DM1 and DM2 gene loci of the family;2)amplified the DM1 and DM2 loci by PCR a second time and tested by PAGE electrophoresis;3)cloned and sequenced the DM1 loci in some blood samples of DM family members;4)after the DM1 and DM2 loci showed no abnormal expansion of oligonucleotide tandem, successively we calculated the LOD values twice by computer with linkage analysis based on the whole-genome scan whose order was to verifysome new susceptible gene loci linked to DM. Results(1) All the DM1 and DM2 loci in the 31 blood samples of the DM family members were normal testing through forementioned three methods, that is, they showed no abnormal expansion of oligonucleotide tandem;(2) Whole-genome scan and parametric linkage analysis showed that, the LOD values with bilateral microsatellite markers near DM1 or DM2 gene locus were all less than 0.3, in addition those at D1S484, D2S641, D5S471, D5S436, D6S434, D12S79, D14S70, D14S292 were 1.9393(θ=0.0), 1.2857(θ=0.1), 1.1064(θ=0.1), 1.4488(θ=0.0), 1.1298(θ=0.1), 1.6851(θ=0.0), 1.3882(θ=0.1), 1.1212(θ=0.1), 1.7720(θ=0.0), respectively. These markers were some suggestive linkage ones with DM.Conclusions(1) The DM family from shanghai is most likely to have a new susceptible gene locus;(2) The new susceptible gene locus of DM may lie in the forementioned microsatellite markers whose LOD values ranged from 1 to 3.Part Two Exploration of Relationship of a Brain-specific Gene Seizure-related (SEZ)-6 with Inherited Epilepsy and Febrile ConvulsionBackground and objectiveAll sorts of domestic and foreign studies indicate that genetic factor is comparatively important in pathogenesis of epilepsy. Nowadays researchers home found more than one thousand genes that relate to epilepsy, and cloned some few genes or candidate genes of familialinherited epilepsy. The brain-specific gene seizure-related(SEZ)-6 is a membranous protein gene which expressed on brain neurons specially. Its genomic sequence extends over 54kb and contains 17 exons, 16 introns. Early studies indicated that SEZ-6 s espression was increased during a mouse s seizure. The human SEZ-6 gene shares 89% identities with mouse SEZ-6 B gene in amino acid level. Thus the objective of this study is to explore the relationship of human SEZ-6 gene with inherited epilepsy and febrile convulsion. MethodsThrough extracting genomic DNA, amplifying by PCR, sequencing gene segments, we tested gene mutations in SEZ-6 s 17 exons of 161 objects, in which 27 objects were inherited epilepsy cases, 46 were sporadic idiopathic epilepsy cases, 40 were asymptomatic relatives of inherited epilepsy cases(All were the first degree relatives), 21 were febrile convulsion cases, 12 were asymptomaic relatives of febrile convulsion cases(fathers or mothers), 15 were healthy individuals. Results(1) Exon 5 and 8 of SEZ-6 gene have mutation loci, which are mainly insert C homozygotic or heterozygotic mutation (frame shift) at 1435 locus, A/G heterozygotic mutation at 1821 locus, C/T heterozygotic mutation at 1922 locus in many blood samples of the epilepsy cases and their relatives; The other exons have some sporadic mutation loci;(2) The types of mutations are almost heterozygotic mutations;(3) The heterozygotic mutation incidences of exon 5 and 8 have a gradually increasing tendency, when the blood samples belong to asymptomatic relatives of inherited epilepsy cases, idiopathic epilepsy cases(include inherited or non-inherited epilepsy), febrile convulsion cases by turns;...
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