title: [Notions of molecular genetics].
abstract: The human genome consists of 3 x 10(9) pairs of bases per haploid genome, the equivalent of 7 x 10(-12) g/diploid cell. During mitosis, it is visible as 23 pairs of chromosomes (22 pairs of autosomes and 1 pair of sexual chromosomes) which comprise the caryotype. The major part of the DNA is non-coding, repetitive sequences some of which are used as genetic markers. The organisation of a gene coding for a protein is now well known with a 5' regulating region, an alternation of exons and introns and a 3' region which is important for the stability of the messenger RNA. The strategy of genetic analysis of cardiovascular diseases varies with the mode of transmission of the disease: classical genetic linkage analysis between marker and disease for mendellan transmission, more complex strategies for multifactorial diseases using sibling pairs, cases-controls studies, haplotypes analyses. In all cases, the progress in techniques of mutations detection and in physical and genetic mappings of the human genome facilitate the identification of the diseases locus.
authors.affiliation: Laboratoire de biologie moléculaire, Hôpital Broussals, Paris.
authors.forename: X
authors.initials: X
authors.lastname: Jeunemaître
mesh_terms: D001483:Base Sequence; D002318:Cardiovascular Diseases / Q000235:genetics*; D005819:Genetic Markers; D005821:Genetic Techniques; D015894:Genome, Human; D006801:Humans; D008967:Molecular Biology; D008969:Molecular Sequence Data; D009154:Mutation; D011110:Polymorphism, Genetic
chemical_list: D005819:Genetic Markers