scholarly journals Prevalence and Heritability of Handedness in a Hong Kong Chinese Twin and Singleton Sample

2019 ◽  
Author(s):  
Mo Zheng ◽  
Catherine McBride ◽  
Connie Suk-Han Ho ◽  
Jonathan Ka-Chun Chan ◽  
Kwong Wai Choy ◽  
...  
Keyword(s):  
Hong Kong ◽  
Genetic Factors ◽  
Reference Data ◽  
Hand Preference ◽  
Hong Kong Chinese ◽  
Left Handedness ◽  
Left Handed ◽  
Chinese School ◽  
Heritability Analysis ◽  
Definition Of

Left-Handedness prevalence has been consistently reported at around 10% with heritability estimates at around 25%. Higher left-handedness prevalence has been reported in males and in twins. Lower prevalence has been reported in Asia, but it remains unclear whether this is due to biological or cultural factors. Most studies are based on samples with European ethnicities and using the preferred hand for writing as the key assessment. Here, we investigated handedness in a sample of Chinese school children in Hong Kong, including 426 singletons and 205 pairs of twins, using both the Edinburgh Handedness Inventory and Pegboard Task. Based on a binary definition of writing hand, we found a higher prevalence of left-handedness (8%) than what was previously reported in Asian datasets. We found no evidence of increased left-handedness in twins, but our results were in line with previous findings showing that males have a higher tendency to be left-handed than females. Heritability was similar for both hand preference (21%) and laterality indexes (22%). However, these two handedness measures present only a moderate correlation (.42) and appear to be underpinned by different genetic factors. In summary, we report new reference data for an ethnic group usually underrepresented in the literature. Our heritability analysis supports the idea that different measures will capture different components of handedness and, as a consequence, datasets assessed with heterogeneous criteria are not easily combined or compared.

scholarly journals Aetiological factors in left-handedness

2005 ◽  
Vol 133 (11-12) ◽  
pp. 532-534 ◽  
Author(s):  
Sanja Milenkovic ◽  
Goran Belojevic ◽  
Radojka Kocijancic
Keyword(s):  
Genetic Factors ◽  
The Body ◽  
Intrauterine Environment ◽  
Foetal Development ◽  
Ultrasound Exposure ◽  
The Past ◽  
Left Handedness ◽  
Left Handed ◽  
Efferent Pathways ◽  
Genetically Determined

Lateralisation associates the extremities and senses of one side of the body, which are connected by afferent and efferent pathways, with the primary motor and sensory areas of the hemisphere on the opposite side. Dominant laterality denotes the appearance of a dominant extremity or sense in the performance of complex psychomotor activities. Laterality is manifested both as right-handedness or left-handedness, which are functionally equivalent and symmetrical in the performance of activities. Right-handedness is significantly more common than left-handedness. Genetic theory is most widely accepted in explaining the onset of lateralisation. According to this theory, the models of brain organisation asymmetry (anatomical, functional, and biochemical) are strongly, genetically determined. However, the inability to clearly demonstrate the association between genetic factors and left-handedness has led researchers to investigate the effects of the environment on left-handedness. Of particular interest are the intrauterine environment and the factors influencing foetal development, of which hormones and ultrasound exposure are the most significant. It has been estimated that an extra five cases of nonright-handed lateralisation can be expected in every 100 males who were exposed to ultrasound in utero compared to those who were not. Socio-cultural pressure on left-handed individuals was much more severe in the past, which is confirmed by scientific findings that left-handedness is present in 13% of individuals in their twenties, while in less than 1% of individuals in their eighties.

Characteristics of Long Bone DXA Reference Data in Hong Kong Chinese

2004 ◽  
Vol 7 (2) ◽  
pp. 192-200 ◽  
Author(s):  
Kwok Sui Leung ◽  
Kwong Man Lee ◽  
Wing Hoi Cheung ◽  
Edmond Siu Woon Ng ◽  
Ling Qin
Keyword(s):  
Hong Kong ◽  
Reference Data ◽  
Hong Kong Chinese ◽  
Long Bone

scholarly journals Why are some people left-handed? An evolutionary perspective

2008 ◽  
Vol 364 (1519) ◽  
pp. 881-894 ◽  
Author(s):  
V Llaurens ◽  
M Raymond ◽  
C Faurie
Keyword(s):  
Evolutionary Dynamics ◽  
Low Frequency ◽  
Hand Preference ◽  
Human Populations ◽  
Left Handedness ◽  
Left Handed ◽  
Selective Forces ◽  
Negative Frequency Dependent Selection ◽  
Available Information ◽  
First Time

Since prehistoric times, left-handed individuals have been ubiquitous in human populations, exhibiting geographical frequency variations. Evolutionary explanations have been proposed for the persistence of the handedness polymorphism. Left-handedness could be favoured by negative frequency-dependent selection. Data have suggested that left-handedness, as the rare hand preference, could represent an important strategic advantage in fighting interactions. However, the fact that left-handedness occurs at a low frequency indicates that some evolutionary costs could be associated with left-handedness. Overall, the evolutionary dynamics of this polymorphism are not fully understood. Here, we review the abundant literature available regarding the possible mechanisms and consequences of left-handedness. We point out that hand preference is heritable, and report how hand preference is influenced by genetic, hormonal, developmental and cultural factors. We review the available information on potential fitness costs and benefits acting as selective forces on the proportion of left-handers. Thus, evolutionary perspectives on the persistence of this polymorphism in humans are gathered for the first time, highlighting the necessity for an assessment of fitness differences between right- and left-handers.

scholarly journals Genetic basis in motor skill and hand preference for tool use in chimpanzees ( Pan troglodytes )

2015 ◽  
Vol 282 (1800) ◽  
pp. 20141223 ◽  
Author(s):  
William D. Hopkins ◽  
Lisa Reamer ◽  
Mary Catherine Mareno ◽  
Steven J. Schapiro
Keyword(s):  
Pan Troglodytes ◽  
Tool Use ◽  
Motor Skill ◽  
Genetic Basis ◽  
Genetic Factors ◽  
Hand Preference ◽  
Left Handed ◽  
Quantitative Genetic ◽  
Significant Heritability ◽  
Genetic Mechanisms

Chimpanzees are well known for their tool using abilities. Numerous studies have documented variability in tool use among chimpanzees and the role that social learning and other factors play in their development. There are also findings on hand use in both captive and wild chimpanzees; however, less understood are the potential roles of genetic and non-genetic mechanisms in determining individual differences in tool use skill and laterality. Here, we examined heritability in tool use skill and handedness for a probing task in a sample of 243 captive chimpanzees. Quantitative genetic analysis, based on the extant pedigrees, showed that overall both tool use skill and handedness were significantly heritable. Significant heritability in motor skill was evident in two genetically distinct populations of apes, and between two cohorts that received different early social rearing experiences. We further found that motor skill decreased with age and that males were more commonly left-handed than females. Collectively, these data suggest that though non-genetic factors do influence tool use performance and handedness in chimpanzees, genetic factors also play a significant role, as has been reported in humans.

Correlations between Hand Preference and Durations of Hearing for Right and Left Ears in Young Healthy Subjects

1998 ◽  
Vol 86 (2) ◽  
pp. 667-672 ◽  
Author(s):  
Şenol Dane ◽  
Mehmet Bayirli
Keyword(s):  
High School Students ◽  
Healthy Subjects ◽  
Significant Positive Correlation ◽  
Hand Preference ◽  
School Students ◽  
Left Handedness ◽  
Left Handed ◽  
Ear Advantage ◽  
Right Ear Advantage ◽  
The Right

In this study, to test an inference from the 1991 Previc hypothesis that right-handers have a right-ear advantage, the durations of hearing for the right and left ears were compared for 81 right- and 45 left-handed high school students. In the present study, right-handedness was associated with a right-ear advantage and left-handedness was associated with a left-ear advantage. In addition, there was a significant positive correlation between the durations of hearing for the right and left ears and the scores for right-handedness for right-handed subjects. The durations of hearing for the right and left ears were negatively correlated with the left-handedness for left-handed subjects. These results suggest hand preference may be related to asymmetry of aural sensitivity.

Left-Handedness in Obstetrics and Gynecology: A Nationwide Survey of U.S. Trainees and Educators

2021 ◽  
Author(s):  
Christopher P. Moutos ◽  
Daphne D. Arena Goncharov ◽  
Antonio F. Saad ◽  
Gwyn Richardson ◽  
Sangeeta Jain
Keyword(s):  
Online Survey ◽  
Training Programs ◽  
Hand Preference ◽  
Nationwide Survey ◽  
Obstetrics And Gynecology ◽  
P Value ◽  
Chi Square ◽  
Left Handedness ◽  
Left Handed ◽  
Key Points

Objective This study aimed to evaluate the views and influence of left-handedness among obstetrics and gynecology (OBGYN) trainees and educators and to identify perceived obstacles in training by left-handed (LH) trainees. Study Design An online survey was sent to the U.S. Obstetrics and Gynecology training programs. All participants were asked questions on hand preference for various medical and nonmedical activities, as well as on demographics. Participant responses to handedness and their role as a learner or educator directed them toward further questions. Trainees were surveyed on their experience and outlook as a LH physician in OBGYN. Educators were surveyed on their experience and attitudes in working with LH trainees. LH educators were also surveyed on their experience as a LH physician, similar to the LH trainees. Chi-square or Fisher's exact analysis was used as appropriate, with p-value <0.05 considered statistically significant. Results Responses were received from 21 training programs, totaling 304 individuals. Participants included 205 learners (156 right handed and 49 left handed), and 99 faculty (82 right handed and 17 left handed). A lack of LH surgical instrument availability (93.6%) and difficulty using right-handed (RH) instruments (83%) were notable obstacles reported by LH learners. The majority of LH learners (57.4%) did not consider their handedness to be disadvantageous but did note added difficulty when training under RH mentors when compared with training under LH mentors (66%). In contrast to LH educators, RH educators endorsed added difficulty in instructing operative procedures to LH learners (32.1 vs. 13.3%, p = 0.012). Conclusion LH trainees face unique challenges during their OBGYN training. Educators would benefit from guidance on how best to manage these trainees. Educators should work to adapt surgical and procedural techniques to accommodate LH trainees. Key Points

Association between human adenovirus-36 infection, obesity and glycemia in prospective follow-up of Hong Kong Chinese school children

2016 ◽  
Vol 120 ◽  
pp. S184
Author(s):  
Alice Pik Shan Kong ◽  
Kai Chow Chow ◽  
Paul Chan ◽  
Chun Kwok Wong ◽  
Mary Waye ◽  
...  
Keyword(s):  
Hong Kong ◽  
School Children ◽  
Human Adenovirus ◽  
Hong Kong Chinese ◽  
Chinese School ◽  
Adenovirus 36

scholarly journals Temporal changes in obesity and sleep habits in Hong Kong Chinese school children: a prospective study

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Lee-Ling Lim ◽  
Gary Tse ◽  
Kai Chow Choi ◽  
Jihui Zhang ◽  
Andrea O. Y. Luk ◽  
...  
Keyword(s):  
Hong Kong ◽  
Prospective Study ◽  
School Children ◽  
Temporal Changes ◽  
Hong Kong Chinese ◽  
Sleep Habits ◽  
Chinese School ◽  
A Prospective Study

scholarly journals Developmental Risk: Evidence from Large Nonright-Handed Samples

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Filippos Vlachos ◽  
Francois Gaillard ◽  
Kiriazis Vaitsis ◽  
Argiris Karapetsas
Keyword(s):  
Age Groups ◽  
Hand Preference ◽  
Learning Theories ◽  
Spatial Skills ◽  
Developmental Risk ◽  
Left Handedness ◽  
Left Handed ◽  
Complex Figure ◽  
Visual Spatial ◽  
Recruitment Procedure

The aim of the present study is twofold. First, we tested the view that individuals who do not develop a typically strong behavioral laterality are distributed differentially among the two genders across age. Second, we examined whether left handedness and mixed handedness are associated with an elevated risk of some developmental or cognitive deficits. A special recruitment procedure provided norms of the Rey-Osterrieth Complex Figure (ROCF) copy from large samples of left-handed () and mixed-handed () compared to right-handed () schoolchildren and adults (). This graphic task was considered as reflective of the growth of visual-spatial skills and impairment at copying as a developmental risk. Subjects’ hand preference was assessed by the Edinburgh Handedness Inventory. Data analysis indicated that (1) the trend towards consistent right handedness is sex related. Girls are clearly ahead of boys in this lateralization process, and boys are overrepresented in mixed-handed subjects. The greater prevalence of mixed-handed boys compared to girls decreases with age. (2) Performance on drawing the ROCF varies according to age and handedness groups. Mixed-handed subjects scored worse in all age groups. The results are discussed in relation to the hormonal-developmental, neuropathological, and learning theories of lateralization.

Sign in / Sign up

Export Citation Format

Share Document