Genetically environmental indicators

A. Brown, A. Young, J. Budon, L. Christides, G. Clarke, D. Coates and W. Sherwin, 1997. Genetic indicators for state of the environment reporting. Australia state of the environmental technical paper series (environmental indicators). Department of Environment, Sport and Territories, Canbeira. 

These relationships are based on the fact that leucine and cystine are common components of the low-sulfur proteins and that proline and cystine are primary components of the high-sulfur proteins. They further suggest that the cystine content should be about 17 to 18% and that large variations beyond the calculated values for these three amino acids indicate some cause of variation such as genetic, environmental (sunlight exposure), cosmetic treatment, or diet. Variation from these factors is described later. 

The genetic basis for the more common late-onset AD appears more complex. Genetic susceptibility is more sporadic and it may be more dependent on environmental factors.9 The apolipoprotein E (apo E) gene on chromosome 19 has been identified as a strong risk factor for late-onset AD. There are three variants of apo E however, carriers of two or more of the apo E4 allele have an earlier onset of AD (approximately 6 years earlier) compared with non-carriers.9 Only 50% of AD patients have the apo E4 allele, thus indicating it is only a susceptibility marker. 

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