[CYTO] Autosomal Disease: Dominant & Recessive

• range from a small DNA mutation or additional, or subtraction of an entire chromosome or set of chromosomes

  Genetic disorder
• Mary result by point mutation or insertion or deletion entirely inside one gene due to error in DNA replication or environmental factors, such as exposure to teratogens


  GENETIC DISORDER
• three types of inherited disease

  1. Autosomal disorder
  2. Allosomal disorder
  3. Mitochondrial disorder
• Mutation of the autosomes or the numbered chromosomes

  Autosomal disorders
• how autosomal and sex chromosomes does humans have?

  22 autosomal, 1 sex chromosome
• these carry genes that determine somatic characteristics but do not have any influence on sex determination

  autosomal disorder
• Pattern of Inheritance where an affected individual has one copy of a mutant gene and one normal gene on a pair of autosome

  Autosomal Dominant
• Pattern of inheritance where an , and an affected individual has two copies of an abnormal gene and must be present for deceased or trait to develop

  Autosomal recessive
• Gene defect: Achondroplasia

  Fibroblast Growth Receptor 3 (FGR3)
• Surgery to reduce pressure inside brain

  hydrocephaly
• Gene defect: Hypercholesterolemia

  Defect in chromosome 19 and mutation in LDL recepror
• Gene defect: Holoprosencephaly

  Sonic Hedgehog (SHH) Gene
• Gene defect: Huntington’s Disease (Huntington Chorea)

  Huntingtin (HDP) - CAG Trinucleotide Repeats
• Gene defect: Marfan‘s Syndrome

  Fibrilin 1 Gene
• what does a group of Fibrilin 1 create?

  microfibrils
• Gene defect: mytonic dystrophy

  protein Kinase Gene (DMPK)
• Gene defect: Neurofibromatisis I (NF1) (Von Recklinghuasen’s Disease)


  microdeletion at 17q11.2 involving NF1 Gene
• Gene defect: Osteogenesis Imperfecta

  either genes encoding a1 or a2 chains of type I collagen
• Gene defect: Polycystic Kidney Disease (PKD)

  either polycystin-1 (PKD-1) or polycystin-2 (PKD-2) and PKHD-1 Gene
• Gene defect: Cystic Fibrosis

  Cystic Fibrosis Transmembrane Regulator (CTFR)
• Gene defect: Gaucher’s Disease

  single cell GBA gene or beta-glucosidase
• beta-glucosidase causes low levels of?

  glucocerebrosidase
• Gene defect: hemochromatosis

  FHE Gene
• in hemochromatosis, cystin becomes ________ =C282y

  tyrosine
• Gene defect: phenylketonuria (PKU)

  Phenylalanine Hydrolase (PAH) gene
• Gene defect: Tay-Sach‘s Disease

  beta-hexosaminodase A isoenzyme (HEXA)
• Gene defect: Xeroderma Pigmentosum (XP)

  any of 9 genes involved in nucleotide excision repair (locus heterogeneity)
• disorder of bone growth that prevents changes of cartilage to bone

  achondroplasia
• clinical features by:

  • short limbs relative to trunk
  • prominent forehead
  • low nasal root
  • redundant skin fold on arms and legs

  achondroplasia
• prognosis: good


  achondroplasia
• defect in chromosome 19 and a mutation in LDL receptor

  hypercholesterolemia
• clinical features:

  • impaired uptake of LDL
  • elevated levels of LDL Cholesterol, cardiovascular disease, and stroke
  • symptoms more severe in homozygous individuals

  hypercholesterolemia
• abnormality in brain development wherein brain does not divide into left and right hemispheres; can also affect head and face development

  holoprosencephaly
• clinical features:

  • Malformation of the brain (no or reduced evidence of an interhemispheric
  • fissure)
  • Dysmorphic facial features
  • Mental retardation

  holoprosencephaly
• Progressive brain disorder that causes uncontrolled movement, emotional problems, and

  loss of thinking ability

  huntington chorea
• clinical feature:

  • Progressive motor, cognitive, and psychiatric abnormalities

  huntington chorea
• what protein does HDP (huntingtin) make and what purpose do they serve?

  huntingtin, cranial nerve cells
• Disorder that affects the connective tissues in many parts of the body

  marfan syndrome
• clinical features:

  • abnormalities of:
  • skeleton: disproportionate tall stature, scoliosis
  • heart: mitral valve prolapse, aortic dilatation, dissection of ascending aorta
  • Pulmonary System
  • Skin – excessive elasticity
  • Joints - hypermobility
  • Congestive Heart Failure is the frequent cause of death

  marfan syndrome
• Most common form of muscular dystrophy that affects the muscles and other body

  systems that begins in the adulthood (20’s or 30’s)

  myotonic dystrophy