CM-1-Introduction-génétique_-place-des-examens-en-génétique.-Anomalie-de-nombre-autosomes-gonosomes Flashcards
(28 cards)
What is genetics?
Genetics is a clinical-biological medical specialty and a transversal discipline.
What is the basis of a genetic consultation?
The basis of the consultation is to establish a family tree.
What are the different types of genetic diseases?
1) Mendelian monogenic diseases 2) Chromosomal diseases 3) Multifactorial diseases 4) Mitochondrial diseases.
What tools are used in medical genetics?
The tools used include clinical signs, chromosomes (karyotype, in situ hybridization), and DNA (for monogenic diseases).
What is the purpose of genetic counseling?
To evaluate the risk of occurrence or recurrence of a disease or malformation.
What is a family tree in genetics?
A family tree is created by asking questions about family members and specific conditions.
What does a karyotype represent in humans?
The normal karyotype in humans is 46, XY (22 pairs of chromosomes + 1 pair of sex chromosomes).
What is a gene?
A gene codes for a protein.
What is a genetic variant?
A variant is an alteration or change in genetic material.
What are the causes of genetic variants?
1) Exposure to mutagenic agents 2) Spontaneous errors during DNA replication and repair.
What is the difference between somatic and germline variants?
A somatic variant cannot be transmitted to offspring, while a germline variant can be.
What are pathogenic variants?
Pathogenic variants can lead to diseases and can be stable or unstable.
What is a character in genetics?
A character is any observable parameter in an individual, cell, or molecule.
What is the difference between dominant and recessive characters?
A dominant character manifests in heterozygotes, while a recessive character does not.
What are molecular tools used in genetics?
Tools include PCR, restriction enzymes, molecular probes, electrophoresis, Sanger sequencing, and NGS.
What is PCR?
PCR (Polymerase Chain Reaction) amplifies millions of copies of a single DNA or RNA segment in hours.
What is Sanger sequencing?
Sanger sequencing involves denaturing dsDNA, amplifying ssDNA, and using termination nucleotides to read sequences.
What is NGS?
NGS (Next-Generation Sequencing) allows sequencing of dozens to hundreds of genes simultaneously.
What are the definitions of genotype and phenotype?
Genotype is the genetic constitution of an individual, while phenotype is the observable characteristic determined by genotype and environment.
What is genetic linkage?
Genetic linkage is the tendency for two non-homologous genes to be inherited together.
What is linkage analysis?
Linkage analysis shows that a genetic marker allele is preferentially transmitted with a genetic disease.
What are monogenic diseases characterized by?
Monogenic diseases are characterized by their mode of transmission, which depends on chromosomal location and expression.
What are chromosomal diseases?
Chromosomal diseases are linked to imbalances in chromosomal material, visible on a karyotype.
What are multifactorial diseases?
Multifactorial diseases have a genetic component but do not follow Mendelian inheritance and recur in families.
