Lecture 1 Lecture 2
Lecture 1 Genetics The study of variation and how it is inherited. Genotype: genetic constitution of an organism and is dependent entirely on parents. Phenotype: morphological, biochemical and behaviour properties, related to how the environment influences expression of genes § Includes appearance, production of hormones and behaviours Genome: full complement of genetic information stored as DNA sequences Sequencing: taking DNA and working out base sequence of it
Variation
Is cause by environmental factors, genetic factors, or a combination of both. Syndrome Collection of effects (as opposed to one phenotypic effect) § Fetal alcohol syndrome: non genetic handicapping which is a result of consumption of alcohol during pregnancy, however can be influenced by other environmental factors § Huntington disease: neurodegenetive disease on chromosome 4, which the variation resulting from a mutation § Artic fox coat colour: changes according to temperature, therefore the environment is affecting gene expression Epigenetic Changes in gene expression without changes in the DNA sequence § Promoters can regulate the switching on and off of a particular gene § Reporter genes can be used as an indicator of the presence/expression of another gene as it attaches close to the gene of interest.
Lecture 2 DNA Gene: segment of DNA Purines: 2-carbon ring (adenine and guanine) Pyrimidines: 1-carbon ring (thymine and cytosine) § DNA strands are antiparallel due to their polarity Locus: location or position of a gene on the chromosome Nucleosome: the core molecule consists of 8 histone molecules, which DNA loops around twice, and H1 locks DNA into place Euchromatin: loosely coiled chromatin. Genes are exposed and transcription is possible. Heterochromatin: tightly coiled chromatin. Transcription is impeded. 1
Variation
Is cause by environmental factors, genetic factors, or a combination of both. Syndrome Collection of effects (as opposed to one phenotypic effect) § Fetal alcohol syndrome: non genetic handicapping which is a result of consumption of alcohol during pregnancy, however can be influenced by other environmental factors § Huntington disease: neurodegenetive disease on chromosome 4, which the variation resulting from a mutation § Artic fox coat colour: changes according to temperature, therefore the environment is affecting gene expression Epigenetic Changes in gene expression without changes in the DNA sequence § Promoters can regulate the switching on and off of a particular gene § Reporter genes can be used as an indicator of the presence/expression of another gene as it attaches close to the gene of interest.
Lecture 2 DNA Gene: segment of DNA Purines: 2-carbon ring (adenine and guanine) Pyrimidines: 1-carbon ring (thymine and cytosine) § DNA strands are antiparallel due to their polarity Locus: location or position of a gene on the chromosome Nucleosome: the core molecule consists of 8 histone molecules, which DNA loops around twice, and H1 locks DNA into place Euchromatin: loosely coiled chromatin. Genes are exposed and transcription is possible. Heterochromatin: tightly coiled chromatin. Transcription is impeded. 1
