PPT-Chromosomal disorders Farouq

Ababneh MD Geneticist H uman being begins life as a fertilized ovum zygote a diploid cell from which all the cells of the body estimated at about 100 trillion 100 x10 12 in number are . Abnormalities in Chromosomal Number. Abnormalities in Chromosomal Structure:. Rearrangements. Fragile Sites. Define:. nondisjunction. polyploidy. aneupoidy. trisomy. monosomy. Abnormalities in chromosomal number. Teratologic. Disorders. Conditions . Down Syndrome – Trisomy 21. Chromosome 21 codes for collage V1. Clinically. MSK. Joint Laxity. C1/2 instability – flexion/extension views . Scoliosis (bracing for <30 surgery for 50-60) & spondylolisthesis . Genetic disorders can be due to any of the following factors:. A. Monogenetic Disorders: Caused by a mutation in a single gene. Autosomal. recessive alleles:. a. You may be a carrier and not know it, since the dominant allele masks the recessive.. Karyotype. Human Chromosomes. Humans have . 46 . chromosomes arranged in . 23. pairs. Two . sex chromosomes. - determine an individual’s sex. Females . have two copies of the large X chromosome. Males have one X and a smaller Y chromosome. .. Most common X-linked disorders.. Usually . expressed only in males.. Rarely, due to random X-inactivation, a female will express disease, called manifesting . heterozygotes. .. Pattern Of Inheritance:. 12.1 Chromosomal Inheritance . 1. Genes are located on chromosomes; this is called the . chromosome theory of inheritance. .. 12.1 Chromosomal Inheritance. Chromosomes can be categorized as two types:. seals is dominant (A) and the allele for short whiskers is recessive (a).. A short whiskered seal and a long whiskered seal mate and produce 7 offspring. The 7 offspring all have long whiskers. What is the genotype of the long whiskered seal?. Chromosomes. Homologous chromosomes. Gene. Exon. Introns . Locus (loci). Alleles. Heterozygous alleles. Homozygous alleles. Genetic . Pathology. Genetic . pathology deals with the diseases that have genetic origin. It is estimated that . What if it’s NOT just the number?. Gene Mutations. Damaged Chromosomes . –. sometimes a portion of a gene or chromosome is lost or damaged during meiosis. Gene mutation. – a mutation that affects the gene. Over the last few decades, a significant transition has taken place in the etiology of diseases affecting mankind. Environmentally related disorders have decreased & genetic disorders & non-communicable disorders have become a major cause of morbidity and mortality. Prokaryotic cell. Plasmid (ring of DNA. ). 50 x Smaller 0.2-2μm. 50 x Bigger 10-100μm. And small rings of DNA called plasmids. Inside a nucleus. Main differences. Prokaryotes:. SIZE – 50 x smaller than eukaryotes. Human Chromosomes. Human chromosomes. 46 total, 23 pairs. 22 pairs of autosomes. 1 pair of sex chromosomes. Male vs. female. Human Chromosomes. Human chromosomes. 46 total, 23 pairs. 22 pairs of autosomes. Prepared by Rania Naoufal, M.D.. Learning Objectives. Chromosome structure. Chromatin. Chromatin exists in several alternative configurations, depending on what that particular stretch of DNA is doing. Asmaa A. Almukhtar .PHD . Lecturer . Medical Genetic Department. ICCMGR. 2023. Introduction to Chromosomal Analysis. Reading &Writing a Chromosomal Analysis Report. How to write the chromosomal analysis report?.