That is such a vague question that you don't really stand a chance of getting a meaningful answer. Which secretions are we talking about? What organism are we talking about? Unfortunately, as it stands, the question itself doesn't really mean anything so I can't give a proper answer.

1) "Blood group and GenoType compatibility Which bread is right for you? Blood group diet and GenoType Diet compatibility of Artisan Bread Original can be found on the label of each bread, or for more information see the table below" Source and further information: http://artisanbread-abo.com/shop/shop_content.php/coID/0/ 2) "Secretors: In a simplified sense, a secretor is defined as a person who secretes their blood type antigens into body fluids and secretions like the saliva in your mouth, the mucus in your digestive tract and respiratory cavities, etc. Non-Secretors: A non-secretor on the other hand puts little to none of their blood type into these same fluids. As a general rule, in the US about 15-20% of the population are non-secretors with the remaining 80-85% being secretors. Aside from the physical implications centering around whether you have blood type antigens in your body fluids or not, the secretor genetics have additional significance through the effects of gene linkage: In other words, the outcome of your secretor genetics ‘links’ to other seemingly unrelated genes and influences their function. Your secretor status drastically alters the carbohydrates present in your body fluids and secretions in addition to several important aspects of your metabolism and resistance. These factors include the activity of an enzyme called intestinal alkaline phosphatase, the overall composition of bacteria in your intestinal ecosystem, your propensities toward blood clotting, your level of carbohydrate tolerance, and your resistance to certain parasites and yeast. In addition to allowing important diet refinements, knowing your secretor status can help you use nutritional supplements more effectively and intelligently and add to your awareness of illness and metabolic dysfunction you may be prone to because of your secretor genetics." Source and further information: http://www.dadamo.com/knowbase/newbie/a.htm 3) Secretors and non-secretors phenotypes and genotypes: Source and further information: "Human Immunogenetics By Stephen D. Litwin" http://books.google.com/books?id=PL8d-DlIQOEC&pg=PA691&lpg=PA691&dq=genotype+of+secretors&source=bl&ots=CinxukFNS5&sig=3HGOn0rI_1TqjJYAysSVurGZmfA&hl=en&ei=8xGoSYbhIpKT_gaFw63tDw&sa=X&oi=book_result&resnum=1&ct=result 4) "Secretors of any group carry either homozygous SeSe or heterozygous Sese genotype." Source and further information: "Biochemistry By Debajyoti Das" http://books.google.com/books?id=Gx0fZ_DF5BoC&pg=RA1-PA840&lpg=RA1-PA840&dq=genotype+of+secretors&source=bl&ots=kogIGHSL-Y&sig=pJSVot6Fb12ayQUYHBSSUIilwhk&hl=en&ei=lxKoSdfmD8zD_gb7_a3tDw&sa=X&oi=book_result&resnum=10&ct=result