Genetic Influence in Disease (Nursing 3366)

Vocabulary flashcards covering key genetic concepts from the lecture notes.

Genome

The complete genetic makeup of a specific organism (e.g., the human genome).

Human Genome Project (HGP)

A nationwide effort begun in 1990 to map the human genome; goals include identifying about 30,000 genes and addressing ethical, legal, and social issues (ELSI).

Gene

A segment of DNA that codes for a protein or trait and guides development and maintenance of body functions.

Packaging of genes (DNA, chromatin, chromosomes)

DNA in the nucleus forms chromatin; before cell division chromatin condenses into chromosomes.

Chromosome

A rod-shaped structure of condensed chromatin that carries genes and is visible during cell division.

Meiosis

Cell division that produces gametes with 23 chromosomes each, introducing genetic variation.

Mitosis

Cell division that produces two identical somatic daughter cells with 46 chromosomes in humans.

Autosomal chromosomes

The 22 pairs of chromosomes not involved in determining sex; present in both males and females.

Sex chromosomes

The 23rd chromosome pair (X and Y) that determines sex.

Homologous chromosomes

Paired autosomal chromosomes that are similar in shape and carry the same genes at the same loci.

Allele

Alternative forms of a gene at the same locus on homologous chromosomes.

Dominant allele

An allele that usually expresses in the phenotype; represented with a capital letter.

recessive allele

An allele whose effects are typically hidden unless two copies are present; represented with a lowercase letter.

Genotype

The specific combination of alleles an individual has for a trait.

Phenotype

Observable characteristics or traits resulting from genotype and environment.

Homozygous

Having two identical alleles for a given gene (e.g., DD or dd).

Heterozygous

Having two different alleles for a given gene (e.g., Dd).

Autosomal disorder

A genetic disorder caused by a gene on an autosomal chromosome.

Sex-linked disorder

A genetic disorder linked to genes on sex chromosomes, often X-linked and more common in males.

Karyotype

An ordered display of chromosomes as seen during metaphase, used to detect abnormalities.

Locus

The specific location of a gene on a chromosome.

Punnett square

A grid used to predict possible genotypes of offspring from parental alleles for a trait.

Zygote

A fertilized egg containing 46 chromosomes (23 from each parent).

Gamete

A reproductive cell (sperm or egg) with 23 chromosomes.

Codon

A triplet of nucleotides in DNA or RNA that codes for one amino acid.

Mutation

A change in the DNA sequence that can produce defective or altered proteins.

Protein synthesis

The process by which cells translate genetic information into proteins at ribosomes.

Carrier

An individual with one normal and one disease allele; typically phenotypically normal but can pass the disease allele.

Incomplete dominance

A genetic situation where heterozygotes show a phenotype intermediate between the two homozygotes (rare in humans).

Sickle cell disease (example)

A recessive genetic disorder caused by a mutation in the beta-globin gene, leading to abnormal red blood cells and symptoms like dyspnea and pain.

PKU (phenylketonuria)

A classic autosomal recessive metabolic disorder caused by deficiency of phenylalanine hydroxylase.

Turner syndrome

A chromosomal disorder (monosomy X) in females (45,X).

Trisomy 21

Down syndrome; presence of an extra copy of chromosome 21.

Philadelphia chromosome

A chromosomal translocation associated with chronic myelogenous leukemia (CML).

Recombinant DNA

DNA created by combining genetic material from different sources; a cornerstone of genetic engineering and therapeutic applications.

Gene mapping

Determining the precise locations of genes on chromosomes and their relative positions.

Ethical, legal, and social issues (ELSI)

Issues arising from genetic research and genome-era technologies that require consideration.