Developmental Psychology (Psych 350)Professor McDermottWelcome Scholars!• Today’s class topic:Building Blocks of HeredityAnnouncements/Overview• EXAM I: Still on schedule 2/14/14– Review Sessions: 2/12 and 2/13 – Timing and room details coming soon• TA Groups• Building Blocks of Heredity– Genetic Principles– Abnormalities– Twins?The Building Blocks Of Heredity• Deoxyribonucleic Acid (DNA): Blueprint for genetic inheritance• Nucleotide: Repeating basic building block of DNA – nitrogen-based molecules • adenine • thymine• cytosine • guanineKaryotype: Pictorial representation of an individual’s chromosomesPrinciples Of Heredity Transmission• Gene: Large segment of nucleotides – within a chromosome – codes for the production of proteins and enzymes• Allele: Alternate form of a specific gene– provides a genetic basis for many individual differencesPrinciples Of Heredity Transmission• Genotype: Set of genetic traits a person inherits• Phenotype: Set of traits a person actually displaysGenotype: Allele combos result in tongue roll versus no tongue rollPhenotype: Tongue Roll or No tongue rollThe Pattern of Inheritance for Cystic FibrosisThe Building Blocks Of Heredity• X Chromosome: Larger of the two sex chromosomes:– Normally• Females have two (XX)• Males have one (XY)• Y Chromosome: Smaller of the two sex chromosomes:– Normally• Females have none (XX)• Males have one (XY)Gene and Chromosomal Abnormalities• Mutation: Sudden change in molecular structure of a gene• Williams syndrome: – Dominant genetic disorder– Involves the deletion of a set of genes• strong social orientation• good musical ability• unusual linguistic capabilitiesGene and Chromosomal Abnormalities• Sickle Cell Disease: Genetic blood disorder – common in regions of Africa and other areas where malaria is found – and among descendants of the people of these regions• Sickle Cell Trait: Symptoms shown by those possessing a heterozygous genotype for sickle cell anemiaGene and Chromosomal Abnormalities• Phenylketonuria (PKU): Recessive genetic disorder in which phenylalanine (found in artificial sweeteners and other foods) fails to be metabolized– If undetected/untreated can lead to sever brain damageGene and Chromosomal Abnormalities• Fragile X Syndrome: Disorder associated with a pinched region of the X chromosome;– a leading genetic cause of intellectual impairment in males. • Down Syndrome: Disorder of extra chromosomal material on pair number 21- Associated with intellectual impairment - Distinct physical featuresFigure 3.8: Relationship Between Maternal Age and the Incidence of Down SyndromeDevelopmental And Behavior Genetics• Heritability: Proportion of variability in the phenotype estimated to be accounted for by genetic influencesTwin ExampleHave a good