Chapter 18 - Genetic Engineering, Reproductive Techniques

Define "Assisted Reproductive Technology"

A fertility treatment used to achieve pregnancy.

Surgical manipulation of the eggs and sperm.

Define "In Vitro Fertilization" (IVF)

Extract eggs after stimulation; fertilizing them in the lab; then put them back into uterus through cervix.

Who was the first baby conceived through IVF?

Louise Joy Brown

What should one consider before undergoing IVF?

Age

If you've had multiple births

Cost

Reduced surgery

Safety

Survival rates

What is the first step in IVF?

Stimulation/Super ovulation

What is the second step in IVF?`

Egg Retrieval (Follicular aspiration)

What is the third step in IVF?

Insemination & fertilization

- Insemination

- Intracytoplasmic sperm injection (ICSI)

What is the fourth and fifth step in IVF?

Embryo culture (Pre-implantation genetic diagnosis)

Embryo Transfer (to uterus)

Define "Gamete Intrafallopian Transfer" (GIFT)

Uses "laparoscope" to guide unfertilized eggs and sperm (gametes) into fallopian tubes through abdomen.

If a woman has at least one normal Fallopian tube, what ART method is used?

Gamete Intrafallopian Transfer (GIFT)

Define "Zygote Intrafallopian Transfer" (ZIFT)

Fertilizes eggs in laboratory then uses laparoscope to guide them (zygotes) into fallopian tubes.

Define "Surrogacy"

- A surrogate is a woman who agrees to become pregnant with the man's sperm and her own egg.

- The child will be genetically related to the surrogate and male partner.

- After birth, surrogate gives up baby for adoption by parents.

Define "Gestational Carrier"

- For women with ovaries but no uterus.

- Woman uses her own egg, fertilized by man's sperm.

- The embryo is placed inside carrier's uterus.

- Carrier not related to baby and gives them to parent's at birth.

What is Traditional Surrogacy?

Surrogate mother is artificially inseminated by the intended father or a donor

What is Gestational Surrogacy?

Gestational mother is artificially inseminated with a fertilized egg or embryo

What is Embryo Cryopreservation?

The process of storing frozen fertilized egg and sperm at extremely low temperatures for future use

Define "Genetic Screening"

Used to determine whether a couple is at increased risk of having a baby with a hereditary genetic disorder.

What is the genetic screening method "Family History Assessment"?

Doctors ask:

Family member disorders

Cause of death

Health of first/second degree relatives

Miscarriages, stillborn babies

Birth defects

Relative intermarriages

Ethnic background

What is needed during Family History Assessment?

Infoformation on three generations

Sometimes doctors review medical records of relatives who have had a genetic disorder.

What is the genetic screening method "Carrier Screening"?

Involves testing people who do not have symptoms but are at higher risk for carrying a recessive gene for a disorder.

Carrier Screening is only done if..?

- The disorder is very debilitating/lethal

- A reliable screening test is available

- The fetus can be treated / reproductive options are available and acceptable to the parents.

What is the genetic screening method "Pre-Implantation Genetic Diagnosis"? (PGD)

Used to determine if genetic/chromosomal disorders are present in IVF embryos.

What is the genetic screening method "Prenatal Screening"?

Involves testing pre-birth fetus to see if the fetus has certain abnormalities, like certain hereditary or spontaneous genetic disorders.

What is the method of Ultrasonography?

- Non-Invasive

- Deep body structure imaging by recording echoes of ultrasonic pulse waves.

- Waves reflect off of tissue planes with different density.

What is the method of Amniocentesis?

- Invasive

- A needle is passed through the mother's lower abdomen into the amniotic cavity inside the uterus

- Amniotic fluid is removed and analyzed.

- Performed at 15-20 weeks of gestation

What is the method of Chorionic Villi Sampling?

A doctor removes a small sample of chorionic villi.

These are tiny projections making up part of the placenta.

- May be performed as early as 10-12 weeks of pregnancy

What is involved in the method of Measurement of Markers/Quad screen?

Alpha Fetoprotein

- Protein made by a developing baby

HCG

- Placenta

Estriol

- Liver

Inhibin A

- Used to check for Down Syndrome

What is Percutaneous Umbilical Cord Sampling?

- Collect fetal blood from umbilical cord

- Used when rapid chromosome analysis is needed (towards end of pregnancy when ultrasound detects abnormalities)

What are some risks in Percutaneous Umbilical Cord Sampling?

- Fetal loss

- Maternal Rh Sensitization

- Morbidity of the fetus

- Limb defects

What is Newborn Screening?

- Collecting blood drops from newborn

- Performing biochemical testing to see if newborn has a heritable condition