1. Autosomal Recessive Conditions 2. Phenylketonuria (PKU) lack an enzyme to process phenylalanine amino acid build up of PHE in urine and blood causes mental deficiencies, motor problems blood test at birth to identify PKU babies specialized PHE-free formula warnings on foods made with aspartame 3.Cystic Fibrosis: (CF) 1 in 2500 Caucasian births 1 in 25 Caucasians is a carrier severe lung congestion (mucus), frequent lung infections ineffective pancreas  no digestion or absorption of most nutrients abnormal liver function 1. Albinism no melanin (pigment) in hair, eyes, skin high risk of skin cancer very poor vision

2. 4. Tay-Sachs lysosomes in brain cells lack enzyme to digest lipids lipids accumulate in brain tissue  cells swell, die degeneration of nervous system high allele frequency in European Jewish population 1 in 25 Jewish Americans are carriers of allele pre-natal screening; carriers have 50% of enzyme very few Tay-Sachs babies born to Jewish parents 5. Sickle Cell Anemia defective hemoglobin gene: 1 nucleotide is wrong,  1 amino acid is incorrect RBC’s will turn sickle shape under low O 2 conditions block blood vessels, very painful 1 in 10 African Americans is a carrier of the gene

3. Autosomal Dominant Conditions 1. Huntington’s Disease: central nervous system problem make too much Huntington protein  damages brain cells dementia, balance problems, delusions symptoms begin ~ 40 years of age child of Huntington’s parent has 50% chance of getting it 2.Marfan Syndrome: defect with fibrilin (in connective tissue of heart, eye and long bones) tall, thin, long arms and legs, long, slender fingers, enlarged aorta 3.Achondroplasia: defects in growth of long bones dwarfism  short arms and legs but normal torso large head (compared to body) all are hybrid (AA is lethal)

4. Sex-Linked Recessive Conditions 1.Hemophilia inability to clot blood lack normal gene for clotting factor 8 protein) injections of clotting factor 8 after cut or injury clotting factor protein genetically engineered in bacteria person may bleed to death from minor cuts, bruises HIV contamination of clotting factor in early 80’s 2.Muscular Dystrophy progressive muscle wasting defect in dystrophin protein abnormal dystrophin causes muscle cell membranes to rupture during contraction  muscle degeneration onset of symptoms around 4  wheelchair by 12  cardiac muscle gives out by 20  patient death

5. Non-disjunction Conditions 1. Down’s Syndrome = Trisomy 21 short, stocky body, wide neck, mental deficiencies, large tongue Non-disjunction in egg OR translocation of #21 onto #14 2.Edward’s Syndrome = Trisomy 18 motor problems and mental deficiencies congenital heart disease death often in infancy 3.Patau’s Syndrome = Trisomy 13 cleft lip and palate polydactyly (extra digits) microencephaly (small head) 4.Cri-du-chat deletion of piece of chromosome #5 “cat-like” cry severe mental and physical abnormalities

6. 5. Turner’s Syndrome: XO short stature, wide neck lack ovary development (sterile) narrow aorta 6. Klinefelter’s Syndrome: XXY male with lowered fertility, some breast development long legs, short torso, wide hips sparse facial and chest hair other forms are: XXXY and XXXXY additional X’s increase severity of phenotype 7. Super Male: XYY 1 in 1000 male births usually tall extra testosterone most XYY males do not know their genotype 8. XXX: Trisomy X most cases are normal, slight increase in sterility