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M Z Cader

Publications and source records attributed to M Z Cader.

9 recordsLinked to original sources
PubMed2005

A genome-wide screen and linkage mapping for a large pedigree with episodic ataxia.

Episodic ataxias are ion channel disorders characterized by attacks of incoordination. The authors performed a genome-wide screen in a large pedigree segregating a novel episodic ataxia and found significant linkage on 1q42 with a multipoint lod score of 3.65. Haplotype analysis and fine mapping yielded a peak 2-point lod score of 4.14 and indicated a 4-cM region on 1q42 that is likely to harbor an episodic ataxia gene.

Adolescent↗
PubMed2004

TCR beta polymorphisms and multiple sclerosis.

A total of 267 families with two or more siblings with multiple sclerosis (MS) were genotyped with 14 restriction fragment length polymorphisms at the TCR beta locus. A nonparametric linkage analysis of the data showed no evidence for linkage to this locus (mlod=0.11). No significant allelic or haplotype transmissions were observed in the total sample of 565 patients. After stratification for the presence of HLA DRB1*15, an association was observed between the BV25S1*1-BV26S1*1-BV2S1*1 haplotype and MS (P=0.00089). This was not significant upon correction for multiple comparisons. It was also not significant when the haplotype frequency in affected individuals was compared to a normal control sample (P=0.77). Furthermore, the associated haplotype was followed-up in an independent sample of 97 nuclear families with a single DRB1*15-positive child with MS. The BV25S1*1-BV26S1*1-BV2S1*1 haplotype did not show significant evidence for transmission distortion but the same trend was seen (P=0.21). There were no significant associations observed in the DRB1*15-negative patients and no detectable difference was seen in the DRB1*15-positive BV25S1*1-BV26S1*1-BV2S1*1 association when comparing different subgroups based on clinical course of MS. These results show no evidence for linkage and fail to establish an association between MS susceptibility and the TCR beta locus.

Female↗
PubMed2003

Genetic loading in familial migraine with aura.

Migraine with aura (MA) arises from a combination of genetic and environmental factors. The sibling risk, age at onset, and aura type were compared in 54 MA probands categorised by family history of MA. Three family types were ascertained each having an MA proband and: (1) an MA parent and MA offspring (three generation; n=15), (2) either an MA parent or an MA offspring (two generation; n=20), and (3) neither an MA parent nor an MA offspring (one generation; n=19). The crude recurrence risk to siblings of probands was 2.7-fold higher in three generation compared with two generation MA families (chi(2)=6.24, p=0.0125) and 4.8-fold higher in three generation compared with one generation MA families (chi(2)=9.95, p<0.002). The mean age at onset decreased with an increase in genetic load. The MA probands from three generation families were significantly younger than probands from the one generation families (F=5.14, p=0.030). MA probands from three generation families were more likely to report more than one type of aura than MA probands from two generation families (chi(2)=4.44, p=0.035). The significant difference in genetic loading and the earlier age at onset in the three generation families add further evidence for a genetic basis for MA and the difference in sibling risks demonstrates that the MA population is heterogeneous.

Adult↗
PubMed2002

Migraine with aura is not linked to the FHM gene CACNA1A or the chromosomal region, 19p13.

Two microsatellite markers, tightly linked to CACNA1A, were genotyped in migraine with aura (MA) families to determine if this gene, which underlies the 19p13 linked forms of familial hemiplegic migraine, is also linked to MA. Two-point parametric lod and nonparametric linkage scores did not support linkage. Transmission disequilibrium testing provided no evidence for linkage of MA to CACNA1A. In a large dataset of 64 Canadian MA families, the authors did not find evidence to support an MA susceptibility gene in the region of 19p13.

Calcium Channels↗
PubMed2002

A multigenerational family with multiple sclerosis.

We report a family with 15 individuals affected with multiple sclerosis present in three and possibly four generations. The segregation of multiple sclerosis within this pedigree is consistent with an autosomal dominant mode of inheritance with reduced penetrance. The clinical characteristics of the affected individuals are indistinguishable from those seen in sporadic multiple sclerosis with respect to sex ratio, age at onset, onset symptom, MRI and clinical course. Eleven of 14 cases (78.6%) were positive for the known multiple sclerosis-associated major histocompatibility complex (MHC) Class II HLA DRB1*15 allele. Parametric linkage analysis gave a non-significant LOD score of 0.31 (theta; = 0.33) for the DRB1 gene. However, among 11 affected children with at least one DRB1*15 bearing parent, all 11 out of 11 received at least one copy of this known susceptibility allele. A transmission disequilibrium test analysis was significant for the DRB1*15 allele within this single family; P = 0.0054. The inheritance pattern in this family suggests the presence of a single major locus responsible for multiple sclerosis susceptibility, with DRB1 acting as an important modifier. This family could be an important resource for the identification of a multiple sclerosis susceptibility gene.

Adolescent↗
PubMed2001

An autosomal dominant disorder with episodic ataxia, vertigo, and tinnitus.

The authors report an autosomal dominant episodic ataxia that is clinically distinct from the other episodic ataxias. Vestibular ataxia, vertigo, tinnitus, and interictal myokymia are prominent; attacks are diminished by acetazolamide. Linkage analyses of markers flanking the EA1 and EA2 loci demonstrate genetic exclusion from the other autosomal dominant episodic ataxias. The authors suggest EA3 for periodic vestibulocerebellar ataxia and EA4 for the disorder described here.

Adolescent↗
PubMed1996

Ethnic differences in pre-admission levels of physical activity in patients admitted with myocardial infarction.

BACKGROUND: Regular exercise is generally considered to reduce the risk of coronary heart disease. Reduced levels of physical activity in Indo-Asians may partly explain why patients from this ethnic group sustain so many heart attacks. AIM: To investigate ethnic differences in pre-admission levels of physical activity amongst patients admitted with myocardial infarction and triggers for the acute cardiac event. DESIGN: Cross-sectional study using standard Baecke questionnaire, which provided a semi-quantitative work score, sport score, leisure score and total activity score of general daily activities, with additional questions on activity at the onset of chest pain. SETTING: Coronary Care Unit, City Centre Teaching Hospital. PATIENTS AND RESULTS: We studied 100 consecutive patients (76 males, mean age 62.3 years, S.D. 12.5; 74 caucasians, 26 Indo-Asians) admitted with myocardial infarction. Most patients were engaged in sedentary activities, including lying in bed (25%), sitting (19%), watching television (14%) and sleeping (6%), whilst only 21% of patients were engaged in physical activity at chest pain onset; there were, however, no ethnic differences in activity at chest pain onset. There was a diurnal variation in chest pain onset, with the mode between 08:00 and 10:00 h. As the mean age of Indo-Asians was significantly lower than caucasians in the whole group (56.3 vs. 64.4 years; t-test, P < 0.002), the Baecke questionnaire analysis was confined to only male patients aged < 70 years (n = 56). Indo-Asian patients with myocardial infarction were found to have a significantly lower overall physical activity score (3.78 vs. 5.33; P = 0.003), leisure time physical activity (2.43 vs. 2.74; P < 0.05) and sporting score (0.14 vs. 0.82; P < 0.01) when compared to caucasians, despite a similar mean age and body mass index. CONCLUSION: The majority of myocardial infarction patients were engaged in sedentary activities at chest pain onset. Although there were no differences between caucasians and Indo-Asians in activity at symptom onset, Indo-Asian patients had a significantly lower overall physical activity score, leisure time physical activity and sporting score compared to caucasians. The lower general physical activity amongst Indo-Asians may in part contribute to the high prevalence of ischaemic heart disease amongst this ethnic group.

Activities of Daily Living↗