Immediate verbal recall and familial dementia risk: population-based study of over 4000 twins

Abstract

ObjectiveTo investigate the effect of familial risk for dementia on verbal learning by comparing cognitively healthy twins who had demented co-twins with cognitively healthy twins who had cognitively healthy co-twins.Methods4367 twins aged ≥65 years including 1375 twin pairs (533 monozygotic (MZ), 823 dizygotic (DZ) and 19 unknown zygosity pairs) from a population-based Finnish Twin Cohort participated in a cross-sectional telephone assessment for dementia and in a single free recall trial of a 10-item word list.ResultsCognitively healthy twins with demented co-twins (n=101 pairs) recalled less words than cognitively healthy twins with cognitively healthy co-twins (n=770 pairs) after adjusting for age, sex and education, B=− 0.44, 95% CI (−0.73 to −0.14), p=0.003. The effect size was similar in MZ (n=31) twins (3.88 vs 4.29 words, B=−0.41, 95% CI (−0.96 to 0.13)) and DZ (n=66) twins (3.70 vs 4.17 words, B=−0.47, 95% CI (−0.84 to −0.10)). The heritability estimate of immediate recall (IR) was 0.37, 95% CI (0.21 to 0.43).ConclusionsThe results demonstrate that familial risk for dementia is reflected in the IR performance of cognitively healthy older persons. The finding of poorer IR performance in non-affected siblings compared with the general population, together with substantial heritability of IR, supports IR as a useful endophenotype for molecular genetic studies of dementia.

The Older Finnish Twin Cohort — 45 Years of Follow-up

“…These two data collections, collectively called MEMTWIN, have cognitive data available from a total of 4429 twins with a participation rate of 67% (Lindgren et al, 2019). Of these, 3614 have genotype data.…”

Evaluation of molecular inversion probe versus TruSeq® custom methods for targeted next-generation sequencing

“…In total, 166 samples from patients diagnosed with diabetic and idiopathic neuropathy were tested by MIPs-NGS and TSCA-NGS. For 70 of these patients, exons and exon-flanking intron sequences of SCN9A, SCN10A, and SCN11A genes were analyzed by Sanger sequencing to validate MIPs-NGS and TSCA-NGS methods [23]. Local Medical Ethical Committees of Fondazione IRCCS Istituto Neurologico "Carlo Besta" (Italy), Maastricht University Medical Center (the Netherlands), University of Manchester (United Kingdom) and the Deutsche Diabetes Forschungsgesellschaft EV (Germany) approved this study.…”

“…Coding exons and exon-flanking intronic regions of SCN9A, SCN10A and SCN11A of 70 patients were amplified by PCR and sequenced by Sanger sequencing as previously described [23], to assess the sensitivity and specificity both targeted-NGS methods.…”

“…Current inability to identify high-risk individuals hinders development and application of therapies to counteract neuropathic pain and to address targeted prevention strategies. Pathogenic variants in voltage-gated sodium channel (VGSC) genes expressed in the peripheral nociceptive pathway such as SCN9A, SCN10A, and SCN11A have been reported to play a key role in neuropathic pain [20][21][22][23].…”

Association of neuroinflammation with episodic memory: a [11C]PBR28 PET study in cognitively discordant twin pairs

“…Cognitively discordant same-sex twin pairs born in 1938–44 were recruited from the older Finnish Twin Cohort study using a telephone interview including the telephone assessment for dementia and the modified Telephone Interview for Cognitive Status instruments in 2013–17 ( Lindgren et al , 2019 ). A total of 1110 same-sex twin pairs were invited to participate in the telephone interview.…”