Medical Genetics

  1. Cytogenetics
    1. Chromosome Structure and Analysis
      1. Chromosome Banding Techniques
        1. G-banding
          1. Giemsa Staining
            1. Trypsin Treatment
              1. Light and Dark Bands
              2. Q-banding
                1. Quinacrine Staining
                  1. Fluorescent Microscopy
                    1. AT-Rich Regions
                    2. R-banding
                      1. Reverse Banding
                        1. Heat Treatment
                          1. GC-Rich Regions
                          2. C-banding
                            1. Constitutive Heterochromatin
                              1. Centromeric Regions
                                1. Satellite DNA
                              2. Karyotype Nomenclature
                                1. International System for Human Cytogenomic Nomenclature
                                  1. ISCN Guidelines
                                    1. Standardized Terminology
                                      1. Nomenclature Updates
                                      2. Interpreting Karyotype Results
                                        1. Normal Karyotype Notation
                                          1. Abnormal Karyotype Description
                                            1. Breakpoint Designation
                                        2. Numerical Chromosome Abnormalities
                                          1. Mechanisms of Nondisjunction
                                            1. Meiosis I Errors
                                              1. Homolog Separation Failure
                                                1. Maternal Age Effect
                                                2. Meiosis II Errors
                                                  1. Sister Chromatid Separation
                                                  2. Maternal Age Effect
                                                    1. Increased Risk with Age
                                                      1. Cohesin Deterioration
                                                        1. Oocyte Aging
                                                      2. Autosomal Trisomies
                                                        1. Trisomy 21
                                                          1. Clinical Features
                                                            1. Intellectual Disability
                                                              1. Characteristic Facial Features
                                                                1. Congenital Heart Defects
                                                                  1. Increased Cancer Risk
                                                                  2. Genetic Mechanisms
                                                                    1. Nondisjunction (95%)
                                                                      1. Robertsonian Translocation (4%)
                                                                        1. Mosaicism (1%)
                                                                      2. Trisomy 18
                                                                        1. Clinical Features
                                                                          1. Severe Intellectual Disability
                                                                            1. Growth Retardation
                                                                              1. Multiple Malformations
                                                                                1. Poor Prognosis
                                                                              2. Trisomy 13
                                                                                1. Clinical Features
                                                                                  1. Severe Intellectual Disability
                                                                                    1. Holoprosencephaly
                                                                                      1. Polydactyly
                                                                                        1. Cardiac Defects
                                                                                    2. Sex Chromosome Aneuploidies
                                                                                      1. Turner Syndrome
                                                                                        1. Clinical Features
                                                                                          1. Short Stature
                                                                                            1. Ovarian Dysgenesis
                                                                                              1. Cardiac Abnormalities
                                                                                                1. Renal Abnormalities
                                                                                              2. Klinefelter Syndrome
                                                                                                1. Clinical Features
                                                                                                  1. Tall Stature
                                                                                                    1. Hypogonadism
                                                                                                      1. Gynecomastia
                                                                                                        1. Learning Difficulties
                                                                                                      2. Triple X Syndrome
                                                                                                        1. Clinical Features
                                                                                                          1. Mild Phenotype
                                                                                                            1. Increased Height
                                                                                                            2. 47,XYY Syndrome
                                                                                                              1. Clinical Features
                                                                                                                1. Tall Stature
                                                                                                                  1. Behavioral Issues
                                                                                                                2. Polyploidy
                                                                                                                  1. Triploidy
                                                                                                                    1. 69 Chromosomes
                                                                                                                      1. Embryonic Lethality
                                                                                                                        1. Hydatidiform Mole
                                                                                                                        2. Tetraploidy
                                                                                                                          1. 92 Chromosomes
                                                                                                                            1. Early Embryonic Death
                                                                                                                        3. Structural Chromosome Abnormalities
                                                                                                                          1. Balanced vs. Unbalanced Rearrangements
                                                                                                                            1. Balanced Rearrangements
                                                                                                                              1. No Gain or Loss
                                                                                                                                1. Usually Phenotypically Normal
                                                                                                                                  1. Reproductive Risks
                                                                                                                                  2. Unbalanced Rearrangements
                                                                                                                                    1. Gain or Loss of Material
                                                                                                                                      1. Phenotypic Consequences
                                                                                                                                        1. Developmental Abnormalities
                                                                                                                                      2. Deletions
                                                                                                                                        1. Terminal Deletions
                                                                                                                                          1. End of Chromosome
                                                                                                                                            1. Single Breakpoint
                                                                                                                                            2. Interstitial Deletions
                                                                                                                                              1. Internal Chromosome Segment
                                                                                                                                                1. Two Breakpoints
                                                                                                                                                2. Cri-du-chat Syndrome
                                                                                                                                                  1. 5p Deletion
                                                                                                                                                    1. Characteristic Cry
                                                                                                                                                      1. Intellectual Disability
                                                                                                                                                      2. 22q11.2 Deletion Syndrome
                                                                                                                                                        1. DiGeorge Syndrome
                                                                                                                                                          1. Cardiac Defects
                                                                                                                                                            1. Immunodeficiency
                                                                                                                                                              1. Psychiatric Disorders
                                                                                                                                                            2. Duplications
                                                                                                                                                              1. Tandem Duplications
                                                                                                                                                                1. Adjacent Copies
                                                                                                                                                                  1. Direct Orientation
                                                                                                                                                                  2. Interspersed Duplications
                                                                                                                                                                    1. Non-adjacent Copies
                                                                                                                                                                      1. Scattered Distribution
                                                                                                                                                                    2. Inversions
                                                                                                                                                                      1. Paracentric Inversions
                                                                                                                                                                        1. Not Including Centromere
                                                                                                                                                                          1. Dicentric and Acentric Products
                                                                                                                                                                          2. Pericentric Inversions
                                                                                                                                                                            1. Including Centromere
                                                                                                                                                                              1. Duplication-Deletion Products
                                                                                                                                                                            2. Translocations
                                                                                                                                                                              1. Reciprocal Translocations
                                                                                                                                                                                1. Exchange Between Non-homologs
                                                                                                                                                                                  1. Balanced Carriers
                                                                                                                                                                                    1. Unbalanced Offspring
                                                                                                                                                                                    2. Robertsonian Translocations
                                                                                                                                                                                      1. Acrocentric Chromosomes
                                                                                                                                                                                        1. Centromere Fusion
                                                                                                                                                                                          1. Down Syndrome Risk
                                                                                                                                                                                        2. Ring Chromosomes
                                                                                                                                                                                          1. Terminal Deletions
                                                                                                                                                                                            1. End-to-End Fusion
                                                                                                                                                                                              1. Instability Issues
                                                                                                                                                                                              2. Isochromosomes
                                                                                                                                                                                                1. Identical Arms
                                                                                                                                                                                                  1. Centromere Division
                                                                                                                                                                                                    1. Turner Syndrome Variant
                                                                                                                                                                                                    2. Clinical Consequences of Structural Abnormalities
                                                                                                                                                                                                      1. Gene Disruption
                                                                                                                                                                                                        1. Position Effects
                                                                                                                                                                                                          1. Dosage Imbalance

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                                                                                                                                                                                                      2. Patterns of Inheritance

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                                                                                                                                                                                                      4. Molecular Genetics and Diagnostics