wk3.Genetics.slides w vo.pptx
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GENETICS PATHOPHYSIOLOGY – NURS 3203 CHROMOSOMES 23 PAIRS TOTAL CONTAIN GENETIC INFORMATION SEX CHROMOSOME NUCLEOTIDES IN DNA (DOUBLE HELIX) & RNA PATTERNS...
GENETICS PATHOPHYSIOLOGY – NURS 3203 CHROMOSOMES 23 PAIRS TOTAL CONTAIN GENETIC INFORMATION SEX CHROMOSOME NUCLEOTIDES IN DNA (DOUBLE HELIX) & RNA PATTERNS OF INHERITANCE MADE OF 3 PARTS: SUGAR, HOMOZYGOUS PHOSPHATE, NITROGENOUS BASE DOMINANT FOUR BASES IN DNA RECESSIVE ADENINE (A) HETEROZYGOUS GUANINE (G) KARYOTYPE CYTOSINE (C) THIAMINE (T) (URACIL IN RNA) GENOTYPE CODON – 3 BASE-PAIR CODE PHENOTYPE FOR PROTEIN SYNTHESIS MITOCHONDRIAL GENES AND INHERITANCE SMALL AMOUNTS OF DNA ARE PRESENT IN MITOCHONDRIA INHERITED DIFFERENTLY THAN GENES ON CHROMOSOMES; ARE NOT TRANSMITTED FROM PARENT TO CHILD LIKE CHROMOSOMES HEREDITARY DISEASES RESULTING FROM MITOCHONDRIAL DNA MUTATIONS ARE INHERITED DIFFERENTLY FROM GENETIC MUTATIONS CARRIED ON GENE THERAPY EXTENSION OF THE PRINCIPLES OF RECOMBINANT DNA TECHNOLOGY NORMAL GENE INSERTED INTO A DEFECTIVE CELL LACKING AN ENZYME OR STRUCTURAL PROTEIN TO COMPENSATE FOR THE MISSING OR DYSFUNCTIONAL GENE CRISP-R: CLUSTERED REGULARLY INTERSPACED SHORT PALINDRO MIC REPEATS GENETIC AND CONGENITAL DISORDERS CAUSED BY A MUTATION MULTI-FACTORIAL TRANSCRIPTION MISTAKE BY MRNA – DELETIONS, INSERTIONS, INVERSIONS, MISPLACEMENTS 6000 SINGLE GENE DEFECTS CHARACTERIZED BY THE PATTERNS OF TRANSMISSION CHROMOSOMAL DISORDERS MAY BE RELATED TO ABNORMALITY IN CHROMOSOMAL NUMBER AND/OR STRUCTURE THAT OCCURS IN MEIOSIS ACCOUNT FOR MOST EARLY ABORTIONS MORE THAN 60 SYNDROMES TRISOMY 21 (DOWN’S SYNDROME) RISK INCREASES WITH MATERNAL AGE CAUSED FROM NONDISJUNCTION DURING MEIOSIS MANIFESTATIONS: SMALL SQUARE HEAD, UPWARD SLANT OF EYES, SMALL LOW-SET EARS, FAT PAD ON BACK OF THE NECK, OPEN MOUTH WITH PROTRUDING TONGUE, SIMIAN CREASE, VARYING DEGREES OF MENTAL RETARDATION, AND BEHAVIORAL ISSUES TRISOMY 21 (DOWN’S SYNDROME) ALSO ASSOCIATED WITH CONGENITAL HEART DEFECTS, OCULAR ISSUES, LEUKEMIA, RESPIRATORY COMPLICATIONS, GASTROINTESTINAL COMPLICATIONS, HYPOTHYROIDISM. 50% OF PATIENTS WITH DOWN’S SYNDROME DEVELOP ALZHEIMER'S DISEASE BY AGE 50. DIAGNOSIS: PARENTAL SCREENING INCLUDING AMNIOCENTESIS, HORMONE LEVELS, 4D ULTRASOUND. TREATMENT: SYMPTOMATIC AND SUPPORTIVE. https://www.physio-pedia.com/File:DS_features.jpg FIGURE 01.F28: DOWN SYNDROME Courtesy of Sarah Coulter-Danner AUTOSOMAL DOMINANT DISORDERS TRANSMITTED FROM AN AFFECTED PARENT TO OFFSPRING REGARDLESS OF GENDER 50% CHANCE OF TRANSMISSION UNAFFECTED DO NOT PASS ON THE DISORDER DELAYED ONSET EXAMPLES: MARFAN SYNDROME, MULTIPLE NEUROFIBROMATOSIS, ACHONDROPLASIA AUTOSOMAL DOMINANT DISORDERS MARFAN SYNDROME DISORDER OF CONNECTIVE TISSUE MUTATION ON CHROMOSOME 15 (FBN1) AFFECTS EYES, SKELETON, AND CARDIOVASCULAR SYSTEM DIAGNOSIS HISTORY, PHYSICAL EXAMINATION, SKIN BIOPSY (PRESENCE OF FIBRILLIN), GENETIC TESTING TREATMENT SURGICAL INTERVENTION FOR CARDIAC COMPLICATIONS GLASSES/SURGICAL INTERVENTION FOR VISION CORRECTION FIGURE 01.F24: MARFAN SYNDROME Courtesy of Rick Guidotti/Positive Exposure/National Marfan Foundation AUTOSOMAL DOMINANT DISORDERS MULTIPLE NEUROFIBROMATOSIS NEUROGENIC TUMORS TWO FORMS TYPE 1: DEFECT ON CHROMOSOME 17 (NF1); SUBCUTANEOUS LESIONS, CAFÉ-AU-LAIT SPOTS (AT LEAST 6 AT BIRTH), FRECKLES, SCOLIOSIS, EROSIVE BONE DEFECTS, AND NERVOUS SYSTEM TUMORS TYPE 2: DEFECT ON CHROMOSOME 22 (NF2); TUMORS OF THE ACOUSTIC NERVE TREATMENT PALLIATIVE REMOVAL OF TUMORS https://www.aboutkidshealth.ca/article?contentid=864&language=english FIGURE 01.F25: NEUROFIBROMATOSIS TYPE 1 © SPL/Science Source AUTOSOMAL RECESSIVE DISORDERS RARE BOTH MEMBERS OF GENE PAIR ARE AFFECTED AFFECTS BOTH GENDERS USUALLY CAUSED BY A DEFICIENT ENZYME EXAMPLES: PKU AND TAY-SACHS AUTOSOMAL RECESSIVE DISORDERS: PKU MUTATION ON CHROMOSOME 12 (PAH GENE) LEADS TO AN ERROR IN CONVERTING PHENYLALANINE TO TYROSINE APPEARS NORMAL AT BIRTH THEN FAILS TO MEET MILESTONES PROGRESSIVE NEUROLOGICAL DECLINE IF UNTREATED, CAN LEAD TO SEVERE INTELLECTUAL DISABILITY AUTOSOMAL RECESSIVE DISORDERS: PKU DIAGNOSIS SERUM PHENYLALANINE AT 3 DAYS OLD TREATMENT AVOID HIGH PROTEIN FOODS PHARMACOLOGIC INTERVENTIONS ENZYME THERAPY AUTOSOMAL RECESSIVE DISORDERS: TAY- SACHS PROGRESSIVE DISORDER DUE TO MUTATION OF HEXOSAMINIDASE A NECESSARY TO METABOLIZE CERTAIN LIPIDS LIPIDS ACCUMULATE, DESTROYING AND DEMYELINATING NERVE CELLS NERVE CELL DESTRUCTION LEADS TO A PROGRESSIVE MENTAL AND MOTOR DETERIORATION MOST ARE OF JEWISH DECENT AUTOSOMAL RECESSIVE DISORDERS: TAY- SACHS APPEARS NORMAL AT BIRTH, THEN DIAGNOSIS: HISTORY, PHYSICAL THE INFANT BEGINS TO MISS EXAMINATION, AND LOW SERUM AND MILESTONES AMNIOTIC HEXOSAMINIDASE A PROGRESSES TO SEIZURES, LEVELS MUSCULAR RIGIDITY, AND NO CURE BLINDNESS GENETIC COUNSELING SUGGESTED USUALLY FATAL BY 3-4 YEARS OF AGE SEX-LINKED DISORDERS SEX-LINKED DISORDERS ARE ALMOST ALWAYS X LINKED. MALES HAVE A 50% CHANCE OF GETTING THE DISORDER FROM THEIR MOTHER. FEMALES HAVE A 50% CHANCE OF BEING CARRIERS. ALL DAUGHTERS OF AFFECTED MALES WILL BE CARRIERS, BUT NONE OF THEIR SONS. EXAMPLES: FRAGILE X SYNDROME, TURNER SYNDROME, KLINEFELTER SYNDROME FRAGILE X SYNDROME ASSOCIATED WITH A SINGLE TRINUCLEOTIDE GENE (FMR1) SEQUENCE ON THE X CHROMOSOME, WHICH IS REPEATED > 200 TIMES PLAYS A ROLE IN SYNAPSE DEVELOPMENT MANIFESTATIONS: LONG FACE WITH LARGE MANDIBLE, LARGE EARS, LARGE TESTICLES, MENTAL RETARDATION, LEARNING DISABILITIES, SPEECH DELAYS, CONNECTIVE TISSUE DISORDERS, BEHAVIORAL ISSUES, AND AUTISM SPECTRUM DISORDER FRAGILE X SYNDROME DIAGNOSIS: HISTORY, PHYSICAL EXAMINATION, GENETIC TESTING TREATMENT: SUPPORTIVE FIGURE 01.F26: FRAGILE X SYNDROME https://www.sciencephoto.com/media/779034/view/fragile-x- syndrome-illustration MONOSOMY X (TURNER’S SYNDROME) DELETION OF ALL OR PART OF AN X—OCCURS SPONTANEOUSLY SPECIFIC GENE(S) ASSOCIATED: NOT KNOWN NO Y CHROMOSOME, SO FEMALE ONLY MANIFESTATIONS: GONADAL STREAKS INSTEAD OF OVARIES, SHORT STATURE, NECK WEBBING, SMALL LOWER JAW, DROOPING EYELIDS, SMALL FINGERNAILS, AND WIDELY SPACED NIPPLES MONOSOMY X (TURNER’S SYNDROME) ALSO ASSOCIATED WITH COARCTATION OF THE AORTA, VISION ISSUES, HEARING LOSS, RENAL AND SKELETAL ABNORMALITIES, INFERTILITY, AND INCREASED RISK FOR INFECTIONS NO MENTAL RETARDATION PRESENT DIAGNOSIS: HISTORY, PHYSICAL EXAMINATION, CHROMOSOMAL TESTING, AND SERUM HORMONE LEVELS TREATMENT: ESTROGEN AND GROWTH HORMONES © https://medizzy.com/feed/19558391 FIGURE 01.F29: TURNER'S SYNDROME TRISOMY X (KLINEFELTER’S SYNDROME) ONE OR MORE EXTRA X ALSO ASSOCIATED WITH CHROMOSOMES WITH THE LEARNING DISABILITIES, PRESENCE OF THE Y BEHAVIORAL PROBLEMS, SEXUAL MALE APPEARANCE DYSFUNCTION, PULMONARY DISEASE, VARICOSE VEINS, OFTEN UNDETECTED OSTEOPOROSIS, AND BREAST MANIFESTATIONS: GYNECOMASTIA, CANCER SMALL TESTES AND PENIS, TALL TREATMENT: TESTOSTERONE STATURE, INCREASED WEIGHT, AND SPARSE BODY HAIR FIGURE 01.F30: KLINEFELTER'S SYNDROME MULTIFACTORIAL INHERITANCE DISORDERS RESULT FROM AN INTERACTION BETWEEN ENVIRONMENTAL AND GENETIC FACTORS LESS PREDICTABLE EXTREMELY COMMON MAY BE EXPRESSED AT BIRTH OR LATER EXAMPLES: CLEFT LIP/PALATE, CLUBFOOT, CONGENITAL DISLOCATION OF HIPS, CONGENITAL HEART DEFECTS, PYLORIC STENOSIS, URINARY TRACT MALFORMATIONS, DIABETES MELLITUS, HYPERTENSION, CANCER, AND PSYCHIATRIC DISORDERS MULTIFACTORIAL INHERITANCE DISORDERS CLEFT LIP AND PALATE IMPROPER FORMATION OF SOFT TISSUES OF MOUTH AND LIPS UNILATERAL OR BILATERAL DEFORMITIES LEAD TO FEEDING AND NUTRITIONAL ISSUES MATERNAL SMOKING, DIABETES, AND SEIZURE MEDICATION USE (FIRST TRIMESTER) ARE IMPORTANT RISK FACTORS DIAGNOSIS: PRENATAL ULTRASOUND TREATMENT: SURGERY, SPEECH THERAPY FIGURE 01.F27: CLEFT LIP AND PALATE Courtesy of Leonard V. Crowley, MD, Century College ENVIRONMENTALLY INDUCED CONGENITAL DISORDERS PERIODS OF FETAL VULNERABILITY BETWEEN THE THIRD AND NINTH WEEKS OF GESTATION TERATOGENIC AGENTS ENVIRONMENTAL FACTORS THAT ADVERSELY AFFECT THE DEVELOPING FETUS CHEMICALS AND DRUGS, INFECTIOUS AGENTS, RADIATION OTHER DISORDERS OF INFANCY LOW BIRTH WEIGHT OR IMMATURITY AT BIRTH INTERRUPTION OF THE PLACENTAL OXYGEN SUPPLY BIRTH INJURIES
