A twin study of the etiology of high readingability

The present study examined the etiology of highreading ability in an overall sample of 350twin pairs in which at least one member of 100pairs (54 MZ, 46 DZ) had a reading compositescore one standard deviation above the sample mean. These highreaders also had significantly higher scoresthan the rest of the sample on Full Scale,Verbal and Performance IQ scores, as well as onmeasures of phoneme awareness, orthographiccoding, phonological decoding, and verbalshort-term memory. The MZ proband-wiseconcordance rate for high group membership wassignificantly higher than the DZ proband-wiseconcordance rate and further behavioralgenetic analyses corroborated that high readingability is partly due to genetic influence(h² _g = 0.55 ± 0.22). Bivariatemultiple regression analyses demonstrated thathigh phonological awareness, orthographiccoding, phonological decoding, and short-termverbal memory skills all share significantcommon genetic influence with high readingability. These results suggest that readingability and its cognitive correlates are on acontinuous distribution, with both extremes ofthe distribution being similarly heritable. They also support the hypothesis that the samecognitive processes that are associated withdyslexia are important for the development ofhigh reading ability.     

实验准备视角下医学细胞生物学和遗传学实验教学改革探索

本文分析了医学院校细胞生物学与遗传学实验教学中存在的不足,并从实验准备视角提出开放实验准备教学、优化实验教学内容、提高实验技术人员素质三方面的改革措施。实践证明,实验教学改革能调动学生参与科学研究的积极性,增强学生的动手能力,提升学生的科研素质和创新精神。     

Risk for reading disability as a function of parental history in three family studies

Inverse Bayesian analyses were applied to data from three large family studies of reading disability to estimate the posterior probability that an offspring will be affected, given that a parent reported a history of learning problems. Prior analyses presented elsewhere (Pennington et al., 1990), suggest that family transmission in these three studies is consistent with major gene or polygene influence. Posterior probability rates are presented in this paper for male to female sex ratios of 3.5:1 and 1:1, with population incidences estimated at 0.05 and 0.10. Results indicate that offspring risk rates are significantly elevated if a parent reports a history of RD. Specifically, an offspring's risk was increased 2 to 80 times over population expectancies when there was an affected parent. While the posterior probabilities and relative risk rates were fairly similar across studies, there was also some variation, which may reflect the different genetic mechanisms operating in these families. This study concludes that both absolute and relative risks are sufficiently increased in families with RD parents to warrant use of family history as a component in clinical evaluation. It is also evident from these results that consideration of the apparent mode of genetic transmission in families may provide even better information as to offspring risk, when family history is obtained.     

浅谈遗传学教学中几个知识点的归纳与总结

遗传学是生物科学和生物技术专业的一门重要的基础课。如何提高学生对遗传学的学习兴趣以及把握学习方法显得至关重要。对遗传学的相关教学内容的数据统计、性别决定、非等位基因相互作用等采用归纳与总结的方法,对知识点进行重新梳理,得出规律,起到提纲挈领的作用,有利于提高学生记忆效率。     

运动天赋与运动选材相关研究

选材是训练成功的基础,确立科学合理的选材指标体系是科学选材的保证和前提,运动能力的遗传学规律为运动员的科学选材提供了理论依据,教练员可以根据不同专项运动员对运动机能的不同要求,将那些具有从事某些运动特殊天赋的少年儿童选拔出来,并给予科学的训练,使他们先天的能力得到充分的发挥和发展。     

在生物类专业高等数学教学中增设遗传学计算例子的探索

生物类专业的高等数学教材中,生物方面的例子几乎没有。本文研究在其中增设遗传学的计算例子,加强专业的针对性,提高学生学习高等数学的兴趣。根据高等数学的内容,增设了数列、极限、求导等方面的例子。寓生物于数学,方便老师在教学中运用。     

SNP的检测方法及其在农作物遗传育种中的应用

SNP（单核苷酸多态性）在生物基因组中具有数量多、分布广等特点,是目前广泛应用的第3代分子标记,在现代生物研究方面具有重要的应用价值。本研究综述了SNP的检测方法及其在农作物遗传育种中的应用。     

Content and timing of feedback in a web-based learning environment: effects on learning as a function of prior knowledge

This study investigated the effectiveness of different types of feedback content (elaborate versus global) and feedback timing (immediate versus delayed) for learning genetics in a web-based learning environment as a function of learners' prior knowledge. It was hypothesized that learning outcomes of students with low prior knowledge would be fostered by immediate elaborate feedback, whereas those of students with more prior knowledge would be enhanced by delayed global feedback. Students' perceptions of the feedback they received were explored. Results showed a significant positive effect of global feedback on learning outcomes for higher prior knowledge learners, although those who received elaborate feedback gave a higher appreciation rating. The findings are discussed in terms of implications for the design and delivery of feedback in web-based learning environments.     

Mannose-binding lectin 2 gene polymorphism and susceptibility to upper respiratory tract infection among endurance athletes

Abstract

The aim of this study was to investigate the influence of mannose-binding lectin 2 (MBL2)-exon-1 gene polymorphisms on upper respiratory tract infection (URTI) incidence among endurance athletes. To this end, 100 healthy elite male athletes participating in the study were classified as either healthy or prone to frequent URTI. Blood samples, DNA isolation, multiplex polymerase chain reaction (PCR) and conventional PCR-RFLP were performed. Genomic DNA was extracted from peripheral leukocytes of whole blood samples using the QIAmp DNA Blood Mini Kit. For comparison of the distribution of genotypes between two groups and for estimating odds ratios (OR) for URTI susceptibility in relation to the MBL2-exon-1 polymorphism, Pearson's chi-square and logistic regression method were used, respectively. The MBL2-exon-1 genotype distribution differed between athletes with URTI and healthy athletes (χ² = 7.81, p = 0.02). The AO and AO + OO genotypes of MBL2 were observed at a greater frequency in the illness-prone group compared with the healthy group (34.04% vs. 11.32%). In conclusion, findings from this study have identified a potential role of genetic variation in influencing the risk for URTI in athletic populations and single-nucleotide polymorphisms (SNPs) in the MBL2-exon-1 genes were associated with an altered risk profile. These measures may have a predictive value in the identification of individuals who are more likely to experience recurrent infections when exposed to high physical stress in the areas of athletic endeavour.     

Genetic influences of sports participation in Portuguese families

Abstract

To estimate familial aggregation and quantify the genetic and environmental contribution to the phenotypic variation on sports participation (SP) among Portuguese families. The sample consisted of 2375 nuclear families (parents and two offspring each) from different regions of Portugal with a total of 9500 subjects. SP assessment was based on a psychometrically established questionnaire. Phenotypes used were based on the participation in sports (yes/no), intensity of sport, weekly amount of time in SP and the proportion of the year in which a sport was regularly played. Familial correlations were calculated using family correlations (FCOR) in the SAGE software. Heritability was estimated using variance-components methods implemented in Sequential Oligogenic Linkage Analysis Routines (SOLAR) software. Subjects of the same generation tend to be more similar in their SP habits than the subjects of different generations. In all SP phenotypes studied, adjusted for the effects of multiple covariates, the proportion of phenotypic variance due to additive genetic factors ranged between 40% and 50%. The proportion of variance attributable to environmental factors ranged from 50% for the participation in sports to 60% for intensity of sport. In this large population-based family study, there was significant familial aggregation on SP. These results highlight that the variation on SP phenotypes have a significant genetic contribution although environmental factors are also important in the familial resemblance of SP.