Female Genitourinary SystemFemale Genitourinary SystemExternalExternal: Vulva aka “perineum”; from mons pubis to anus. : Vulva aka “perineum”; from mons pubis to anus.

Mons pubis = fat pad located over symphysis pubis.Mons pubis = fat pad located over symphysis pubis.

Labia majora –outer folds of skin within mons pubis. Labia majora –outer folds of skin within mons pubis.

Labia minora –2 folds inside labia majora. Labia minora –2 folds inside labia majora.

Clitoris anterior to labia minora; func.similar to penis; contains Clitoris anterior to labia minora; func.similar to penis; contains

erectile tissue.erectile tissue.

Either side of urethra: Skene’s glands > secretions > keep Either side of urethra: Skene’s glands > secretions > keep

vaginal area moist. vaginal area moist.

Either side of vagina: Bartholin’s glands >secrete mucous Either side of vagina: Bartholin’s glands >secrete mucous

during intercourse. Visible with infection. during intercourse. Visible with infection.

Cervix:Cervix: neck of uterus. neck of uterus. ““OsOs”” opening opening Never pregnant: small, round os. + vagina delivery: slit-likeNever pregnant: small, round os. + vagina delivery: slit-like

Made of smooth muscle & connective tissue [2 types of Made of smooth muscle & connective tissue [2 types of epithelium: squamous & columnar]. epithelium: squamous & columnar]. Cells tested during Pap & analyzed for abnormalities. Cells tested during Pap & analyzed for abnormalities. Func: allows sperm to enter & menstrual flow to exit. Func: allows sperm to enter & menstrual flow to exit.

Uterus:Uterus: upside down hollow pear-shaped muscle; upside down hollow pear-shaped muscle; Lies in pelvic cavity; tilts forward Lies in pelvic cavity; tilts forward ““antevertedanteverted””. Holds & . Holds & protects growing fetus.protects growing fetus.3 layers: endometrium, myometrium, perimetrium. 3 layers: endometrium, myometrium, perimetrium. Fundus: top portion; EndometriumFundus: top portion; Endometrium sheds w.menses. sheds w.menses.

OvariesOvaries: : small, oval-shaped organs [~ 2 cm by 3 cm by 1 small, oval-shaped organs [~ 2 cm by 3 cm by 1 cm] cm]

Influenced by FSH & LH - “gonadotropic Influenced by FSH & LH - “gonadotropic hormones; causes ovum to grow & mature hormones; causes ovum to grow & mature monthly. monthly.

Produced by anterior pituitary gland.Produced by anterior pituitary gland.Ovaries connect to uterus by fallopian tube. Ovaries connect to uterus by fallopian tube. Develop & release ova & produce hormones:Develop & release ova & produce hormones:estrogen, progesterone & testosterone estrogen, progesterone & testosterone [small amts.in females]. [small amts.in females].

Ova released from ovary, enters fallopian tube, Ova released from ovary, enters fallopian tube, travels to uterus.travels to uterus.

Puberty: Anterior pituitary releases FSH & LH > Puberty: Anterior pituitary releases FSH & LH > androgens & estrogen [both females & males] > androgens & estrogen [both females & males] > secondary sex characteristics.secondary sex characteristics. Reproductive age begins here; girls get menses Reproductive age begins here; girls get menses

earlier now - d/t PNV & better diets .earlier now - d/t PNV & better diets . Age 10-12 not uncommon.Age 10-12 not uncommon.

GametogenesisGametogenesis: production of specialized sex : production of specialized sex cells [gametes]. Male and Female. cells [gametes]. Male and Female.

By age 22, ~ 300,000 eggs remain; by By age 22, ~ 300,000 eggs remain; by menopause, none remain. menopause, none remain.

Cyclic monthly release of eggs > “menses” or Cyclic monthly release of eggs > “menses” or they are absorbed.they are absorbed.

## of chromosomes in nucleus of ## of chromosomes in nucleus of gametes halved from 46 to 23 ( meiosis) gametes halved from 46 to 23 ( meiosis) [22 autosomes & 1 sex chromosome – [22 autosomes & 1 sex chromosome – either X or Y]. either X or Y].

In females occurs before ovulation each In females occurs before ovulation each month & in males occurs before puberty. month & in males occurs before puberty.

Ovum have X chromosome & sperm have Ovum have X chromosome & sperm have either X or Y. Male determines sex: either X or Y. Male determines sex: XX=female; XY = male.XX=female; XY = male.

Male Genitourinary SystemMale Genitourinary System

ExternalExternal: penis & scrotum.: penis & scrotum. Male reproductive organ = penis.Male reproductive organ = penis. Shaft made of vascular erectile tissue. Shaft made of vascular erectile tissue. ““Glans” tip/end of penis; covered by thin skin aka Glans” tip/end of penis; covered by thin skin aka

“foreskin”. “foreskin”. Circumcision removes foreskin. Urethral “meatus” –slit-Circumcision removes foreskin. Urethral “meatus” –slit-

like opening located @ tip. Leads to tube “urethra” that like opening located @ tip. Leads to tube “urethra” that reaches up to bladder. Func: reproduction & urination.reaches up to bladder. Func: reproduction & urination.

Scrotum [thin walled sac] posterior & encloses testes.Scrotum [thin walled sac] posterior & encloses testes. Surface > folds of skin aka “rugae” =normal. Protects Surface > folds of skin aka “rugae” =normal. Protects

testes, epididymis, & vas deferens. testes, epididymis, & vas deferens.

Internal GenitaliaInternal Genitalia: scrotal sac divided in 2.: scrotal sac divided in 2.

One One testistestis on each side. O on each side. Oval shaped.val shaped. Produce sperm & testosterone.Produce sperm & testosterone. Suspended by spermatic cords. Suspended by spermatic cords. Spermatic cord: blood vessels, lymphatic Spermatic cord: blood vessels, lymphatic

vessels, nerves, cremasteric muscle vessels, nerves, cremasteric muscle [[very very sensitive to temp.changes - controls rise & sensitive to temp.changes - controls rise & relaxation of scrotum in hot & cold weather]relaxation of scrotum in hot & cold weather]

Keeps temp.cooler than normalKeeps temp.cooler than normal

Epididymis: lies over testes. Allows Epididymis: lies over testes. Allows spermatozoa to mature.spermatozoa to mature.

Vas deferens [part of epididymis] allows Vas deferens [part of epididymis] allows sperm to exit. sperm to exit.

Semen = sperm & secretions from glands Semen = sperm & secretions from glands [Cowper’s/prostate/bulbourethral[Cowper’s/prostate/bulbourethral]]

BreastsBreasts

Pair of Pair of mammary glandsmammary glands 1] production & storage of milk = “lactation” 1] production & storage of milk = “lactation” 2] sexual stimulation. Male breasts = no func.2] sexual stimulation. Male breasts = no func. Lie over pectoral muscles of anterior chest wall Lie over pectoral muscles of anterior chest wall Extend from 2Extend from 2ndnd to 6 to 6thth rib & from sternum to rib & from sternum to

midaxillary line. midaxillary line. Male & female breasts similar til puberty.Male & female breasts similar til puberty. Estrogen & progesterone, released by ovaries, Estrogen & progesterone, released by ovaries,

causes growth of breast tissue @ puberty.causes growth of breast tissue @ puberty. Divided into 4 quadrantsDivided into 4 quadrants

Breast skin smooth; color varies with skin tone.Breast skin smooth; color varies with skin tone. Nipple centrally located; microscopic openings Nipple centrally located; microscopic openings

[excretory ducts]>allow milk to pass [lactation] [excretory ducts]>allow milk to pass [lactation] Areola darkened, circular area around nipple; Areola darkened, circular area around nipple;

has raised nodules [sebaceous glands] has raised nodules [sebaceous glands] “Montgomery tubercles” - oily substance cleans “Montgomery tubercles” - oily substance cleans nipple. nipple.

Areola enlarges & darkens; does not return to Areola enlarges & darkens; does not return to normal size & color > preg. normal size & color > preg.

Color depends on person’s skin tone.Color depends on person’s skin tone.

Internal Structure: 3 types of tissueInternal Structure: 3 types of tissue

1] Glandular: functional >> breast milk prod.1] Glandular: functional >> breast milk prod. Each breast 15-20 lobes Each breast 15-20 lobes Each lobe contain alveoli > made up of acinar Each lobe contain alveoli > made up of acinar

cells. cells. Alveoli secrete milk into lactiferous ducts where Alveoli secrete milk into lactiferous ducts where

it passes > lactiferous sinuses [milk reservoirs] & it passes > lactiferous sinuses [milk reservoirs] & released thru excretory ducts > nipple.released thru excretory ducts > nipple.

2] fat2] fat 3] muscle3] muscle

Amount of breast tissue affected by:Amount of breast tissue affected by:

MenseMenses: Engorgement 3-5 days < menses. s: Engorgement 3-5 days < menses.

Breasts ^ in size, density, sensitivity, & nodularity. Breasts ^ in size, density, sensitivity, & nodularity.

MenopausMenopause: breast tissue becomes less dense & e: breast tissue becomes less dense &

decrease in size [d/t lack of estrogen]. decrease in size [d/t lack of estrogen].

Breast exam best done 1 week > menses. Breast exam best done 1 week > menses.

Pregnancy/Lactation:Pregnancy/Lactation: fuller & firmer; areola fuller & firmer; areola

darkens; nipples erect. Produce colostrum & darkens; nipples erect. Produce colostrum &

breast milk.breast milk.

Review Of Menses:Review Of Menses: Menstrual Cycle has 2 phases: uterine & ovarian.Menstrual Cycle has 2 phases: uterine & ovarian. Uterine PhaseUterine Phase: 1] menses 2] proliferative 3] : 1] menses 2] proliferative 3]

secretorysecretory Menses: ~5 days [shedding of uterine lining]Menses: ~5 days [shedding of uterine lining] Proliferative: thickening of endometrium; day 5-14 Proliferative: thickening of endometrium; day 5-14 Secretory: day 14-28; ↑ progesterone makes Secretory: day 14-28; ↑ progesterone makes

lining rich in nutrients. If no fertilization: lining rich in nutrients. If no fertilization: progesterone & estrogen fall; lining degenerates. progesterone & estrogen fall; lining degenerates. Menses 2-3days later. Menses 2-3days later.

Menstrual flow: blood, mucous, frag.of Menstrual flow: blood, mucous, frag.of endometrial tissue, & unfertilized ovum. endometrial tissue, & unfertilized ovum.

..

Ovulatory PhaseOvulatory Phase: 1] follicular 2] ovulation 3] luteal : 1] follicular 2] ovulation 3] luteal Follicular: Influenced by FSH, one ovum grows & Follicular: Influenced by FSH, one ovum grows &

is surrounded by follicle. Mature graafian follicle is surrounded by follicle. Mature graafian follicle moves to edge of ovary to release egg. moves to edge of ovary to release egg.

Ovulation: occurs > LH surge; follicle ruptures & Ovulation: occurs > LH surge; follicle ruptures & ovum released; waits to be fertilized in ovum released; waits to be fertilized in fallop.tubefallop.tube

Luteal: if not fert.,ovum & corpus luteum shrink. Luteal: if not fert.,ovum & corpus luteum shrink. If fert.,corpus luteum stays til ~10 -12 wks. If fert.,corpus luteum stays til ~10 -12 wks. Produces progesterone to sustain Produces progesterone to sustain fetus/pregnancy until placenta developsfetus/pregnancy until placenta develops

GENETICSGENETICS

Basic ConceptsBasic Concepts

Genetic information stored on tightly coiled Genetic information stored on tightly coiled strands of dexoxyribonicleic acid (DNA) called strands of dexoxyribonicleic acid (DNA) called chromosomes.chromosomes.

Chromosomes composed of DNA, histone Chromosomes composed of DNA, histone proteins [+ charge] & non-histone proteins. proteins [+ charge] & non-histone proteins. Bind very tightly.Bind very tightly.

Chromosomes contain thousands of genes; Chromosomes contain thousands of genes; smallest units of heredity informationsmallest units of heredity information

Cells express only some of their genes. Genes Cells express only some of their genes. Genes expressed determine function of cell. If genes expressed determine function of cell. If genes have incorrect information, defects follow.have incorrect information, defects follow.

Mutations result from changes in DNA Mutations result from changes in DNA sequences.sequences.

Normal number of chromosomes = 46.Normal number of chromosomes = 46. 22 pairs of autosomes & 1 pair of sex 22 pairs of autosomes & 1 pair of sex

chromosomes = 23. “Meiosis” chromosomes = 23. “Meiosis” Female: meiosis: occurs before ovulation Female: meiosis: occurs before ovulation

& in males occurs before puberty & in males occurs before puberty

Human Genome ProjectHuman Genome Project (1990-2003); research on (1990-2003); research on genetic mutations & inherited diseases. genetic mutations & inherited diseases.

Identified ~ 30,000 genes in humansIdentified ~ 30,000 genes in humans Pictorial analysis (karotype) can be performed on any Pictorial analysis (karotype) can be performed on any

tissuetissue. . (phenotype = what’s expressed)(phenotype = what’s expressed)

Genetic disorder can be classified as either Genetic disorder can be classified as either congenital or hereditary congenital or hereditary

Congenital : Present @ birth. Congenital : Present @ birth. Occurs @ Occurs @ conception. Can involve abnormal chromosome #, conception. Can involve abnormal chromosome #, structure, or multifactorial (genes & environment )structure, or multifactorial (genes & environment )

Ex. Vent.septal defect, hypospadius, cleft lip & palateEx. Vent.septal defect, hypospadius, cleft lip & palate.. Hereditary: Predetermined by family hx. Hereditary: Predetermined by family hx.

Transferred from parent to child: Transferred from parent to child: Sickle cell Sickle cell disease, & cystic fibrosis. disease, & cystic fibrosis.

Some Currently Available DNA-Based Some Currently Available DNA-Based Gene TestsGene Tests

Amyotrophic lateral sclerosis Amyotrophic lateral sclerosis (ALS; Lou Gehrig's (ALS; Lou Gehrig's Disease; progressive motor function loss leading to Disease; progressive motor function loss leading to paralysis & death) paralysis & death)

Alzheimer's disease* Alzheimer's disease* (APOE; late-onset variety of (APOE; late-onset variety of senile dementia) senile dementia)

Ataxia telangiectasia Ataxia telangiectasia (AT; progressive brain disorder (AT; progressive brain disorder resulting in loss of muscle control & cancers) resulting in loss of muscle control & cancers)

Congenital adrenal hyperplasia Congenital adrenal hyperplasia (CAH; hormone (CAH; hormone deficiency; ambiguous genitalia & male pseudo-deficiency; ambiguous genitalia & male pseudo-hermaphroditism) hermaphroditism)

Cystic fibrosis Cystic fibrosis (CF; disease of lung & pancreas results (CF; disease of lung & pancreas results in thick mucous accumulations; chronic infections) in thick mucous accumulations; chronic infections)

Cont.Cont. Duchenne muscular dystrophy/Becker Duchenne muscular dystrophy/Becker

muscular dystrophy muscular dystrophy (DMD; severe to mild (DMD; severe to mild muscle wasting, deterioration, weakness) muscle wasting, deterioration, weakness)

Dystonia Dystonia (DYT; muscle rigidity, repetitive (DYT; muscle rigidity, repetitive twisting movements) twisting movements)

Fanconi anemia, group C Fanconi anemia, group C (FA; anemia, (FA; anemia, leukemia, skeletal deformities) leukemia, skeletal deformities)

Factor V-Leiden Factor V-Leiden (FVL; blood-clotting disorder) (FVL; blood-clotting disorder) Fragile X syndrome Fragile X syndrome (FRAX; leading cause of (FRAX; leading cause of

inherited mental retardation) inherited mental retardation) Gaucher disease Gaucher disease (GD; enlarged liver & spleen, (GD; enlarged liver & spleen,

bone degeneration) bone degeneration)

Cont.Cont. Inherited breast and ovarian cancer* Inherited breast and ovarian cancer* (BRCA 1 (BRCA 1

and 2; early-onset tumors of breasts/ovaries) and 2; early-onset tumors of breasts/ovaries) Hereditary nonpolyposis colon cancer* Hereditary nonpolyposis colon cancer* (CA; (CA;

early-onset tumors of colon.early-onset tumors of colon. Hemophilia A and B Hemophilia A and B (HEMA & HEMB; bleeding (HEMA & HEMB; bleeding

disorders) disorders) Hereditary HemochromatosisHereditary Hemochromatosis (HFE; ^^ iron (HFE; ^^ iron

storage disorder) storage disorder) Huntington's disease Huntington's disease (HD; usually midlife (HD; usually midlife

onset; progressive, lethal, degenerative onset; progressive, lethal, degenerative neurological disease) neurological disease)

Cont.Cont. Myotonic dystrophy Myotonic dystrophy (MD; progressive muscle (MD; progressive muscle

weakness; most common form of adult muscular weakness; most common form of adult muscular dystrophy) dystrophy)

Neurofibromatosis type 1 Neurofibromatosis type 1 (NF1; multiple (NF1; multiple benign nervous system tumors that can be benign nervous system tumors that can be disfiguring; cancers) disfiguring; cancers)

Tay-Sachs Disease Tay-Sachs Disease (TS; fatal neurological (TS; fatal neurological disease of early childhood; seizures, paralysis) disease of early childhood; seizures, paralysis)

Phenylketonuria Phenylketonuria (PKU; progressive mental (PKU; progressive mental retardation d/t missing enzyme; corrected by retardation d/t missing enzyme; corrected by diet) diet)

Adult Polycystic Kidney Disease Adult Polycystic Kidney Disease (APKD; (APKD; kidney failure & liver disease) kidney failure & liver disease)

Cont.Cont.

Prader Willi/Angelman syndromes Prader Willi/Angelman syndromes (PW/A; (PW/A; decreased motor skills, cognitive impairment, decreased motor skills, cognitive impairment, early death) early death)

Sickle cell disease Sickle cell disease ( blood cell disorder; chronic ( blood cell disorder; chronic pain and infections) pain and infections)

Spinocerebellar ataxia, type 1 Spinocerebellar ataxia, type 1 (SCA1; (SCA1; involuntary muscle movements, reflex disorders, involuntary muscle movements, reflex disorders, explosive speech) explosive speech)

Spinal muscular atrophy Spinal muscular atrophy (SMA; severe, (SMA; severe, usually lethal progressive muscle-wasting usually lethal progressive muscle-wasting disorder in children) disorder in children)

Thalassemias Thalassemias (anemias - reduced RBC levels) (anemias - reduced RBC levels)

Mendel’s laws: [1866]Mendel’s laws: [1866]

Principles of dominancePrinciples of dominance a. Genes not equal in strengtha. Genes not equal in strength b. Stronger gene produces an observable b. Stronger gene produces an observable

trait; called dominanttrait; called dominant c. Weaker gene; trait not seen; called c. Weaker gene; trait not seen; called

recessiverecessive. Ex. brown eye color dominant . Ex. brown eye color dominant over blue.over blue.

F1 generation always dominantF1 generation always dominant F2 generation produces both dominant & F2 generation produces both dominant &

recessive traits recessive traits

Principle of segregationPrinciple of segregation Paired chromosomes that contain genes Paired chromosomes that contain genes

from both parents separate during meiosis.from both parents separate during meiosis.

Principle of independent assortment :Principle of independent assortment : Pair of one set of genes distributed in Pair of one set of genes distributed in

gametes in random fashion unrelated to othergametes in random fashion unrelated to other

pairs; in other words… pairs; in other words… Chance determines whether maternal or Chance determines whether maternal or

paternal gene travels to specific gamete.paternal gene travels to specific gamete.

How can children from the same parents How can children from the same parents look so different?look so different?

Father's chromosomes >> his mother & father, Father's chromosomes >> his mother & father, Mother's “” >> her mother & father. Mother's “” >> her mother & father. To make sperm cell, ½ of genetic material is contributed.To make sperm cell, ½ of genetic material is contributed. Which half? Which half? When sperm cells form, father's body When sperm cells form, father's body randomlyrandomly chooses chooses

genes from two halves of father's chromosomes. genes from two halves of father's chromosomes. So, every sperm cell contains random mix of So, every sperm cell contains random mix of father's father's

parents' genes. parents' genes. Same thing occurs when forming eggs. Same thing occurs when forming eggs. Therefore,Therefore, each child that a couple produces is each child that a couple produces is random mixrandom mix of the 4 of the 4

grandparents' genes. grandparents' genes.

Categories of Genetic DisordersCategories of Genetic Disorders

Trait determined by 2 genes: one from each parent.Trait determined by 2 genes: one from each parent.Autosomal-dominant:Autosomal-dominant: abnormal gene on autosome. abnormal gene on autosome.

require single copy of gene to be affected. One parent require single copy of gene to be affected. One parent with disease for child to inherit disease. with disease for child to inherit disease.

Bad gene dominates good gene. Bad gene dominates good gene. No "carrier“; everyone with genetic error gets disease. No "carrier“; everyone with genetic error gets disease. Inherited thru non-sex chromosomes, pairs 1-22.Inherited thru non-sex chromosomes, pairs 1-22. Each preg. 50/50 chance of having disease. Each preg. 50/50 chance of having disease. Examples: Neurofibromatosis; adult Polycystic Examples: Neurofibromatosis; adult Polycystic

kidneys; Huntington’s chorea; Marfan syndrome; kidneys; Huntington’s chorea; Marfan syndrome; breast, ovarian, & colon CA .breast, ovarian, & colon CA .

Autosomal Recessive:Autosomal Recessive: 2 abnormal genes to have 2 abnormal genes to have disease.disease.

If 4 children produced & both parents carriers:If 4 children produced & both parents carriers:

STATISTICAL expectation:STATISTICAL expectation: 1 child: 2 normal chromosomes (normal) 1 child: 2 normal chromosomes (normal) 2 children: 1 normal & 1 abnormal chromosome 2 children: 1 normal & 1 abnormal chromosome

(carriers, no disease) (carriers, no disease) 1 child: 2 abnormal chromosomes (+ disease) 1 child: 2 abnormal chromosomes (+ disease)

EACH child: EACH child: 1 in 4 chance1 in 4 chance inheriting disorder & inheriting disorder & 50:50 chance50:50 chance being carrier. being carrier.

Examples: Cystic fibrosis; sickle cell; Albinism; Examples: Cystic fibrosis; sickle cell; Albinism; Tay-Sachs, tendency for venous thrombosis.Tay-Sachs, tendency for venous thrombosis.

X-linked InheritanceX-linked Inheritance: affects genes on X chromosome: affects genes on X chromosome X-linked recessiveX-linked recessive:: No father to son transmission. No father to son transmission. Males with X-linked disorder always give X Males with X-linked disorder always give X

chromosome to daughters. Daughters are carriers.chromosome to daughters. Daughters are carriers. X-linked recessive genes expressed in females if 2 X-linked recessive genes expressed in females if 2

copies of gene (on each X chromosome). copies of gene (on each X chromosome). Y chromosome has no genes.Y chromosome has no genes. In males, need only 1 copy of X-linked recessive gene In males, need only 1 copy of X-linked recessive gene

for disorder to be expressed. Dominant in expression.for disorder to be expressed. Dominant in expression. Males Males never never carriers.carriers. Examples: Hemophilia A; color blindness; Duchenne Examples: Hemophilia A; color blindness; Duchenne

Muscular Dystrophy; Fragile X-linked mental retardation Muscular Dystrophy; Fragile X-linked mental retardation [~290 conditions exist][~290 conditions exist]

X-linked dominant:X-linked dominant: rare. rare. Trait never passed from father to son.Trait never passed from father to son. All daughters of an affected male and normal All daughters of an affected male and normal

female affected. All sons of an affected male and female affected. All sons of an affected male and normal female are normal. normal female are normal.

Males receive gene from mother; usually more Males receive gene from mother; usually more severely affected than females. severely affected than females.

Trait may be lethal in males. No carriers.Trait may be lethal in males. No carriers. Examples: Coffin-Lowry syndrome & Familial Examples: Coffin-Lowry syndrome & Familial

rickets. rickets.

Chromosomal Deviations – CongenitalChromosomal Deviations – Congenital

Deviation: either in # or structure of Deviation: either in # or structure of chromosome.chromosome.

Structural defect can be d/t loss, addition, Structural defect can be d/t loss, addition, rearrangement of genes on chromosome or rearrangement of genes on chromosome or exchange of genes between chromosomes. exchange of genes between chromosomes. Occurs during meiosis.Occurs during meiosis.

Deviations in # of chromosomes involve either Deviations in # of chromosomes involve either gain or loss of entire chromosome during cell gain or loss of entire chromosome during cell division. division.

Monosomy – lacks chromosome; incompatible Monosomy – lacks chromosome; incompatible w. life. Ex. Turner’s syndrome (one X)w. life. Ex. Turner’s syndrome (one X)

Trisomy – extra chromosomeTrisomy – extra chromosome

Cont.Cont.

Most common chromosomal disorder: Trisomy Most common chromosomal disorder: Trisomy 21 aka Down’s Syndrome [95%] 21 aka Down’s Syndrome [95%]

Extra chromosome = # 21. Extra chromosome = # 21. Trisomy 13; lower survival rate.Trisomy 13; lower survival rate. Nondisjunction: pair chromosomes don’t Nondisjunction: pair chromosomes don’t

separate [Down’s]separate [Down’s] Translocation: 2 or more chromosomes Translocation: 2 or more chromosomes

rearrange during meiosis. Too much/too little rearrange during meiosis. Too much/too little chromosomal material is received. Assoc. w. chromosomal material is received. Assoc. w. advanced maternal age [AMA]advanced maternal age [AMA]

Multifactorial Inheritance DisordersMultifactorial Inheritance Disorders genes & environment interact to produce (often) genes & environment interact to produce (often)

“Isolated” birth defect. “Isolated” birth defect. Can be mild to severeCan be mild to severe no inheritance pattern but higher risk of no inheritance pattern but higher risk of

recurrence observed in certain families. recurrence observed in certain families. Examples: risk for spina bifida ↓ with ↑ levels of Examples: risk for spina bifida ↓ with ↑ levels of

folic acidfolic acid in prenatal period. in prenatal period. Rate of HD ^ in moms with hx IDDM. Rate of HD ^ in moms with hx IDDM. ^ FAS with ^ maternal alcohol intake. ^ FAS with ^ maternal alcohol intake. ^ rate cleft lip/palate (in-breeding occurs)^ rate cleft lip/palate (in-breeding occurs) Environmental risks include nutrition, diseases.Environmental risks include nutrition, diseases.

Detection of Genetic DisordersDetection of Genetic Disorders

Preconception ScreeningPreconception Screening

Family Hx: determine disease & birth defect Family Hx: determine disease & birth defect patterns. Take thorough family hx – photos.patterns. Take thorough family hx – photos.

Prenatal TestingPrenatal Testing > 40 years recommended> 40 years recommended Carrier testingCarrier testing -certain ethnic groups -certain ethnic groups ^ incidence diseases: Tay-Sachs, Sickle cell, ^ incidence diseases: Tay-Sachs, Sickle cell,

Cystic FibrosisCystic Fibrosis

StatisticsStatistics: Risk for Trisomy 21 [Down’s]: Risk for Trisomy 21 [Down’s] Age 20-24 = 1/1400 birthsAge 20-24 = 1/1400 births Age 35 = 1/400; Age 40 = 1/100Age 35 = 1/400; Age 40 = 1/100 Age 45 = 1/25; Age 49 = 1/12Age 45 = 1/25; Age 49 = 1/12

Post Delivery:Post Delivery: Biochemical Tests: PKU [NYS mandate]; tests ~ 50 Biochemical Tests: PKU [NYS mandate]; tests ~ 50

genetic and congenital disorders {CF, sickle cell, PKU, genetic and congenital disorders {CF, sickle cell, PKU, congenital hypothyroidism}congenital hypothyroidism}

Newborn Hearing Screen - congenital hearing loss Newborn Hearing Screen - congenital hearing loss Cytologic Studies: DNA studies [karotype]Cytologic Studies: DNA studies [karotype] Dermatoglyphics: study of hand; simian crease in Down Dermatoglyphics: study of hand; simian crease in Down

syndromesyndrome Role of NurseRole of Nurse: offer support & allow to verbalize : offer support & allow to verbalize

feelings; don’t offer “stories” of other pts. Don’t offer false feelings; don’t offer “stories” of other pts. Don’t offer false hope; OK to verify feelings.hope; OK to verify feelings.

Ethical dilemma's may exist.Ethical dilemma's may exist. Non-judgmental approach. Non-judgmental approach.