3/15/2009. Mendelian heredity. Hereditary traits. Examples of traits. Monogenic. Polygenic

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Alexis Simon
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Hereditary traits - traits determined by expression of one or several genes interaction with environment;!!! Role of genetic factors is higher than 50%.

1 Hereditary traits - traits determined by expression of one or several genes interaction with environment;!!! Role of genetic factors is higher than 50%. Hereditary traits may be: - monogenic or polygenic; - monofactorial or multifactorial; - morphological, physiological, biochemical, behavioral. Hereditary traits Monogenic Polygenic - Determined by one gene or a pair of genes; - Usually are monofactorial; - Have mendelian inheritance; - May be normal or pathological; - May be dominant, recessive, co-dominant - Have bimodal distribution - Determined by several genes or pairs of genes; - Are multifactorial; - Have non-mendelian inheritance; - May be normal or pathological; - May be different phenotypes - Have Gaussian distribution Monogenic Rh+ / Rh-; ABO, MN, Xg... Haptoglobines Transferines Secretor / non-secretor Polydactyl / pentadactyl N. phenotype / PKU Coagulation / Hemophilia Etc. Examples of traits Polygenic Skin color Height Mass Blood pressure IQ Fingerprints Diabetes Schizophrenia Etc. Allele D Rh + Allele d Rh - Parents DD x dd Gametes D d F 1 Dd 100% Mendelian heredity Inheritance of Rh Allele D normomorphyc, dominant Allele d amorphyc, recessive P Dd x dd G D d d F 1 Dd 50% dd 50% P G Dd x Dd D d D d F1 DD 25% Dd 50% dd 25% Person 1 Person 2 Person 3 Person 4 A1, Rh+ B, Rh- 0, Rh+ A2B, Rh+ 1

Bombay phenotype A1, Rh +, Secretor A1, Rh +, non-secretor A1A1, Dd, Sese A1A1, Dd, sese Genotype 00 Hh group 0 (antigen H present) Genotype B0 hh Bombay phenotype, group 0 (AB0 antigens ) ABO blood

Mother fetus incompatibility: 1. Mother Rh - is carrier of Anti-D (immunized) 2. Fetus Rh + Alleles Chromosome localization Rh factor D, d 1 Taste sensibility Secretory groups G, g?

2 Bombay phenotype A1, Rh +, Secretor A1, Rh +, non-secretor A1A1, Dd, Sese A1A1, Dd, sese Genotype 00 Hh group 0 (antigen H present) Genotype B0 hh Bombay phenotype, group 0 (AB0 antigens ) ABO blood group system Rh phenotypes: Rh + : Ag D strong immunological properties Ag DU weak immunological properties Effect of position of D gene to C and E Hemolytic disease of newborn (HDNB) and Rh conflict Mother fetus incompatibility: 1. Mother Rh - is carrier of Anti-D (immunized) 2. Fetus Rh + Alleles Chromosome localization Rh factor D, d 1 Taste sensibility Secretory groups G, g? Se, se 19 Antigen H H, h 19 AB0 blood types MONOGENIC NORMAL HUMAN TRAITS 0, A 1, A 2, B 9 Relations between alleles Co-dominance DD, Dd dd GG, Gg gg Genotypes SeSe, Sese sese HH, Hh hh 00 A 1A 1, A 1A 2, A 10 A 2A 2, A 20 BB, B0 A 1B A 2B Phenotypes Rh+ Rh- Taste sensible Taste nonsensible Secretor Non-secretor H antigen Bombay phenotype 0 (I) A 1 (II) A 2 (II) B (III) A 1B (IV) A 2B (IV) 2

3 MN blood types Alleles Chromosome localization Relations between alleles M, N 4 Co-dominance Haptoglobin Hp1, Hp2 16 Co-dominance Xg blood groups Xg(a+), Xg(a-) X MM MN NN Genotypes Hp1Hp1 Hp1Hp2 Hp2Hp2 Xg(a+)Xg(a+), Xg(a+)Xg(a-), Xg(a+)Y M MN N Phenotypes Hp1-1 Hp1-2 Hp2-2 Xg+ 1 O,M,Rh+,Hp1-1 A B, MN,Rh+,Hp1-2 / O,MN,Rh+,Hp2-2 2 A2,MN,Rh-,Hp1-2 B O, M,Rh+,Hp1-1 / A2, MN,Rh+,Hp1-1 3 A1B,MN,Rh-,Hp1-2 C A2, N,Rh-,Hp1-2 / A2B, N,Rh+,Hp1-2 4 A2B,N,Rh+,Hp1-1 D A1, M,Rh+,Hp1-2 / A2B, N,Rh-,Hp1-2 5 O,N,Rh+,Hp2-2 E A1, MN,Rh-,Hp1-1 / A1B, M,Rh-,Hp2-2 Other genes Phenotype 1 Gene interaction Genotype Effect of position Phenotype 2 Environment Phenotype 3 Hh B0 Dd sese Phenotype B, Rh +, non-secretor hh B0 Dd Sese Phenotype 0 Bombay, Rh +, non-secretor HbA Hbs Normal phenotype in normal O 2 concentration HbA Hbs Anemia in condition of hypoxia Allele Complete dominance Non-complete dominance Co-dominance Allele complementation Supra-domination Allele exception: Hemisygotes Genetic imprinting Non-allele Epistasy Gene complementation Effect of position Polymery Complete dominance Aa = AA Allele interaction Non-complete dominance AA>Aa>aa Co-dominance MM MN NN Genomic imprinting selective inactivation of genes depending their orygin Rh Secretor Xg HbA HbA healthy HbA HbS anemia HbS HbS lethal MN AB HLA Allele exception Allele complementarity Ig X linked genes in AA - normal AA1 - normal AA2 - normal A1A1 - mutant A2A2 - mutant A1A2 - normal Aa Aa 3

Non-allele interactions Additive polymery

position Skin color: A1 melanin A2 melanin A3

Nonsecretor Formation of hemoglobin Hearing

4 Non-allele interactions Additive polymery Epistasy Gene complementarity Effect of position Skin color: A1 melanin A2 melanin A3 melanin a amorphyc allele Bombay phenotype Nonsecretor Formation of hemoglobin Hearing CDE (Rhesus factor) A1A1A2aA3A3 A1aA2aA3a IQ Mass Epistasy amorphyc cannot work Gene complementarity Sickle cell anemia Gene complementarity mutant mutant 4

5 Genetic heterogeneity Allelic heterogeneity Locus heterogeneity Allele 1 1 Allele 2 2 Allele 3 3 or or Gene 3 Abnormal trait 5

Codominance. P: H R H R (Red) x H W H W (White) H W H R H W H R H W. F1: All Roan (H R H W x H R H W ) Name: Date: Class:

Codominance. P: H R H R (Red) x H W H W (White) H W H R H W H R H W. F1: All Roan (H R H W x H R H W ) Name: Date: Class: Name: Date: Class: (Exceptions to Mendelian Genetics Continued) Codominance Firstly, it is important to understand that the meaning of the prefix "co is "together" (i.e. cooperate = work together, coexist