Based on an extensive review of twin-, linkassociationiation studies, and reported structural genomic abnormalities associated with these disorders, we have identified seventeen regions on the human genome that can be related to both disorders.
A wealth of clinical and epidemiological studies have examined various aspects of alcohol consumption, generally reported as drinks per a given period of time, and numerous approaches have been used to assess genetic contributions (e.g., twin and linkage studies).
Human twin and family linkage studies as well as animal model studies have confirmed the importance of genetic factors in the individual variance in peak bone mass acquisition, BMD, bone geometry, and metabolism and thus the predisposition to osteoporosis and related fragility fractures.
The likelihood of initiating and persisting in smoking, and ultimately of becoming nicotine dependent, are all influenced by genetic factors, as demonstrated by numerous twin [ 1– 5], linkage [ 6– 9] and candidate gene [ 10– 12] studies.
Twin heritability and linkage studies segregate the genetic and environmental effects based on the assumption that monozygotic twins are genetically identical, and so their phenotypic differences are of environmental origin.
This review will provide an overview on all available studies [family based, twin, candidate gene, linkage, and genome wide association (GWA) studies] shedding light on the role of shared genetic underpinnings of ADHD and ASD.
A twin study using genetic linkage analysis showed significant linkage for lead and suggestive linkage for cadmium, mercury, selenium and zinc (6).
Despite its mostly sporadic onset and a high discordance rate in monozygotic twins, several human linkage studies had been initiated to determine susceptibility genes for this disease.
We studied childhood cancer incidence in a population-based twin cohort using record linkage to the National Registry of Childhood Tumours.
To date, no IIM familial linkage or twin studies have been published, and the 'heritability' of the disease (λs) is unknown.
