Inheritance and Genetics

Basic Patterns of Inheritance Characteristics of parents are transferred to offspringCharacteristics of parents are transferred to offspring Inherited characteristic is not "blended"Inherited characteristic is not "blended" DominantDominant RecessiveRecessive Characteristics of parents are transferred to offspringCharacteristics of parents are transferred to offspring Inherited characteristic is not "blended"Inherited characteristic is not "blended" DominantDominant RecessiveRecessive

Mendel's Laws of Inheritance (mid 1800's) 1. Equal Segregation “Two copies of a gene separate during meiosis into different gametes" Punnett square 1. Equal Segregation “Two copies of a gene separate during meiosis into different gametes" Punnett square P = purple (dominant) p = white (recessive)

Mendel's Laws of Inheritance 2. Independent Assortment “Genes are segregated and inherited independently of other genes" Color and texture 2. Independent Assortment “Genes are segregated and inherited independently of other genes" Color and texture R = round r = wrinkled Y = yellow y = green

Baby Steps through Punnett Squares 1.Determine parent genotypes 2.Write down your "cross" (mating) 3.Draw a p-square 4."Split" the letters for each parent’s genotype and write them "outside" the p-square 5.Determine the possible offspring genotypes and fill in the p-square 6.Summarize results (genotypes & phenotypes of offspring) 7.Bask in the glow of your accomplishment! 1.Determine parent genotypes 2.Write down your "cross" (mating) 3.Draw a p-square 4."Split" the letters for each parent’s genotype and write them "outside" the p-square 5.Determine the possible offspring genotypes and fill in the p-square 6.Summarize results (genotypes & phenotypes of offspring) 7.Bask in the glow of your accomplishment!

Non-Sex Linked Genetically Inherited Human Diseases Autosomal Recessive DisordersAutosomal Recessive Disorders –Symptoms show in homozygous recessive Autosomal Dominant DisordersAutosomal Dominant Disorders –Symptoms show with just 1 allele Autosomal Recessive DisordersAutosomal Recessive Disorders –Symptoms show in homozygous recessive Autosomal Dominant DisordersAutosomal Dominant Disorders –Symptoms show with just 1 allele

Autosomal Recessive Cystic FibrosisCystic Fibrosis Tay-SachsTay-Sachs Sickle-CellSickle-Cell Cystic FibrosisCystic Fibrosis Tay-SachsTay-Sachs Sickle-CellSickle-Cell

Autosomal Recessive Genetic Disorders Tay-Sachs diseaseTay-Sachs disease –Relentless deterioration of mental and physical abilities that commences around six months of age and usually results in death by age four Cystic fibrosisCystic fibrosis –Common disease that affects the entire body, causing progressive disability and often early death. –Symptoms include difficulty breathing, increased mucus production, sinus infections, poor growth and infertility. Tay-Sachs diseaseTay-Sachs disease –Relentless deterioration of mental and physical abilities that commences around six months of age and usually results in death by age four Cystic fibrosisCystic fibrosis –Common disease that affects the entire body, causing progressive disability and often early death. –Symptoms include difficulty breathing, increased mucus production, sinus infections, poor growth and infertility.

Sickle-cell disease (SCD)Sickle-cell disease (SCD) –Characterized by red blood cells that assume an abnormal, rigid, sickle shape. –Sickling decreases the cells' flexibility and results in a risk of various complications. –Some symptoms include chronic pain, decreased immunity, increased risks of stroke and heart failure, kidney failure. Sickle-cell disease (SCD)Sickle-cell disease (SCD) –Characterized by red blood cells that assume an abnormal, rigid, sickle shape. –Sickling decreases the cells' flexibility and results in a risk of various complications. –Some symptoms include chronic pain, decreased immunity, increased risks of stroke and heart failure, kidney failure.

Autosomal Dominant AchondroplasiaAchondroplasia –AA is lethal!!! –Aa = dwarfism –aa = no dwarfism PolydactylyPolydactyly –AA or Aa = extra digits ProgeriaProgeria –Premature aging AchondroplasiaAchondroplasia –AA is lethal!!! –Aa = dwarfism –aa = no dwarfism PolydactylyPolydactyly –AA or Aa = extra digits ProgeriaProgeria –Premature aging

Huntington’s ChoreaHuntington’s Chorea –progressive neurodegenerative genetic disorder, which affects muscle coordination and leads to cognitive decline and dementia. –Typically becomes noticeable in middle age. –Much more common in people of Western European descent than in those from Asia or Africa. Marfan’s SyndromeMarfan’s Syndrome –Genetic disorder of the connective tissue. –Runs from mild to severe. –The most serious complications are the defects of the heart valves and aorta. –May also affect the lungs, eyes, skeleton and the hard palate and sac surrounding spinal cord Huntington’s ChoreaHuntington’s Chorea –progressive neurodegenerative genetic disorder, which affects muscle coordination and leads to cognitive decline and dementia. –Typically becomes noticeable in middle age. –Much more common in people of Western European descent than in those from Asia or Africa. Marfan’s SyndromeMarfan’s Syndrome –Genetic disorder of the connective tissue. –Runs from mild to severe. –The most serious complications are the defects of the heart valves and aorta. –May also affect the lungs, eyes, skeleton and the hard palate and sac surrounding spinal cord

Sickle CellSickle Cell –Malaria Cystic FibrosisCystic Fibrosis –Cholera Tay SachsTay Sachs –Tuberculosis Sickle CellSickle Cell –Malaria Cystic FibrosisCystic Fibrosis –Cholera Tay SachsTay Sachs –Tuberculosis Heterozygote Advantage?

Sex Linked Recessive