Human Genetics Flashcards

Flashcards on Human Genetics

Human Genetics

Study of human genetic variation, applying and interpreting pedigree analysis.

Pedigree Analysis

Inheritance patterns controlled by genotype alleles at a single locus.

Autosomal recessive disorders

Not on a sex chromosome, pairs 1-22 in humans.

Recessive Allele

Codes for malfunctioning protein or no protein version of a specific gene

Heterozygote

Codes for enough protein, normal phenotype; carrier for recessive allele.

Homozygous recessive

Has disorder; most born to parents who are carriers.

Cystic Fibrosis (Normal)

Normal allele codes for transmembrane protein transport of Cl-

Cystic Fibrosis (Recessive)

Protein defective or missing.

Cystic Fibrosis (Homozygous Recessive)

Thick, sticky mucus builds up in many organs.

Hemoglobin

4 polypeptide chains: 2 alpha, 2 beta; single amino acid substitution in beta chains.

Sickle Cell Disease

Abnormal RBCs destroyed. Anemia, low iron, clump, block capillaries, tissue damage & pain.

Heterozygotes (Sickle Cell)

Normal allele normal Hgb, abnormal allele abnormal Hyb, resistance to malaria evolutionary advantage.

Lethal Alleles

If recessive, heritable homozygous recessive death.

Dominant Lethal Alleles

Death often before reproduction; late onset diseases no symptoms until after reproductive age

Huntington's Disease

Death of brain cells, overall deterioration, and death adult onset.

Disomy

Normal 2n state 2 copies of each chromosome homologous pair for each chromosome

Genomic Imprinting

Phenotype depends on whether allele is inherited from mom or dad.

Genetic Testing

Earlier diagnosis of genetic disorder greater chance for preventing.

Phenylketonuria (PKU Normal)

Normal phenylalanine metabolized to tyrosine.

Phenylketonuria (PKU)

Autosomal recessive disorder. Phe metabolized to phenylketones toxic damage to CNS intellectual disability