Genetic Counseling - University Of...
Transcript of Genetic Counseling - University Of...
11/13/2017 1
Genetic Counseling
Brook Croke, M.S., M.P.H.Genetic Counselor, CooperGenomics
UIUC MCB Workshop SeriesNovember 13, 2017
OVERVIEW
11/13/2017 3
EVALUATING GENETIC RISK
GENETICS OF HUMAN DISEASE
THE PATH TO GENETIC COUNSELING
CELL ANATOMY
CHROMOSOMES ARE INSIDE THE NUCLEUS OF OUR CELLS
11/13/2017 4
CHROMOSOME STRUCTURE
11/13/2017 5
ONE CHROMOSOME BEFORE REPLICATION
ONE CHROMOSOME AFTER REPLICATION
Centromere Centromere
“p” Arm “p” Arm
“q” Arm“q” Arm
Two Identical Sister Chromatids
DNA STORAGE
11/13/2017 6
Genes within our DNA provide the instructions for the body to create proteins.Proteins help our body grow, function, and repair itself.
GENETICS OF HUMAN DISEASE
11/13/2017 7
MUTATIONS ARE CHANGES IN GENES
11/13/2017 8
Mutations can be passed down from parents or they can happen sporadically.
SOME MUTATIONS MAKE US UNIQUE
11/13/2017 9
Humans are >99% alike. The remaining ~1% is what makes us each unique. Mutations in some genes lead to differences in traits like hair and eye color. However, some mutations can cause genetic disease.
TYPES OF GENETIC DISEASE
11/13/2017 10
Multifactorial Condition
+
Single-gene Disorder
Chromosome Abnormality
X X Y
AUTOSOMAL DOMINANT INHERITANCE
11/13/2017 11
AUTOSOMAL RECESSIVE INHERITANCE
11/13/2017 12
X-LINKED INHERITANCE
11/13/2017 13
TYPES OF GENETIC DISEASE
11/13/2017 14
Multifactorial Condition
+
Single-gene Disorder
Chromosome Abnormality
X X Y
TYPES OF GENETIC DISEASE
11/13/2017 15
Variations of chromosomal
material
Chromosome Abnormality
X X Y
NONDISJUNCTION
11/13/2017 16
Normal Meiosis I
Normal Meiosis II
Nondisjunction in Meiosis II
Oocytes containing the correct number of chromosomes
Oocytes containing the incorrect number of chromosomes
MONOSOMY
11/13/2017 17
TRISOMY
11/13/2017 18
TRIPLOIDY
11/13/2017 19
COPY NUMBER VARIATION (CNV)
11/13/2017 20
1 copyNormal
0 copiesAbnormal
2 copiesAbnormal
RECIPROCAL TRANSLOCATION
11/13/2017 21
ROBERTSONIAN TRANSLOCATION
11/13/2017 22
NORMAL NONHOMOLOGOUS, ACROCENTRIC CHROMOSOMES
ROBERTSONIAN TRANSLOCATION
Breakage and Rejoining
INVERSION
11/13/2017 23
PARACENTRIC INVERSION(Does not include centromere)
PERICENTRIC INVERSION(Includes centromere)
TYPES OF GENETIC DISEASE
11/13/2017 24
Multifactorial Condition
+
Single-gene Disorder
Chromosome Abnormality
X X Y
MULTIFACTORIAL CONDITIONS
11/13/2017 25
+
GENOTYPE TO PHENOTYPE
11/13/2017 26
PenetranceHow often a genotype correlates to a phenotype
Variable ExpressivityThe same condition has differing
symptoms & severity in different people
X-inactivationRandom inactivation of one
X chromosome in each cell
MosaicismGenetic makeup varies among cells
MOSAICISM
11/13/2017 27
CELL DIVISIONMOSAIC TISSUE
NORMAL CELLS
CELLS WITH GENETIC CHANGE
EVALUATING GENETIC RISK
11/13/2017 28
FAMILY HISTORY
11/13/2017 29
EMPIRIC RISKS: SCHIZOPHRENIA
11/13/2017 30
General Population Risk of Schizophrenia: ~1%
Your risk is increased if you have a family member affected with schizophrenia.
Affected Relative Recurrence Risk (%)
Sibling 7 - 10
Both Parents 45
One Parent 7 - 16
Identical Twin 40 - 50
Fraternal Twin 10 - 18
First Cousin 1 - 2
Data from: Harper PS. Practical Genetic Counseling. 7th ed. Boca Raton: CRC Press; 2010. and March of Dimes. Empiric recurrence risks for common multifactorial conditions. Genetics & Your Practice.
ENVIRONMENTAL RISKS
11/13/2017 31
Advanced Maternal &
Paternal Age (AMA & APA)
Teratogens
THE PATH TO GENETIC COUNSELING
11/13/2017 32
Why Genetic Counseling?
11/13/2017 33
13 million Americans have a genetic disorder
10% of chronic diseases, such as heart conditions, cancer, diabetes, and arthritis, have a significant genetic component
31% of the time, physicians misinterpret results of genetic testing (NEJM 1997. 336(12):823--‐7)
Is this the right career for you?
11/13/2017 34
Genetic counselors work in a variety of settings
Room for movement within the field
There is flexibility in work schedule (work from home options becoming more common)
Patient interaction whether in clinic or working in a laboratory setting
My Experiences
11/13/2017 35
• Private laboratory (CooperGenomics, NxGen MDx)
• University clinics (SIUSOM, UICOMP)
• Illinois Department of Public Health – Newborn Screening Program
• Blog writer – ataxic CP, radiation
Graduate Programs
11/13/2017 36
Almost 40 genetic counseling graduateprograms in the US and Canada
Several new programs under review, online program starting next Fall. Number of students matriculating in 2016(including Canadian schools): 317
No additional clinical training, residency etc., go directly into the job market following graduation from ~2 yr. program
Applying
11/13/2017 37
• 3 letters of recommendation• GRE scores• Shadowing GCs• Volunteer experience (crisis counseling, hospice,
special olympics, etc.)
Preparing for the interview
11/13/2017 38
• Become familiar with hot topics in genetics• https://www.cdc.gov/genomics/update/current.htm• Familiarize yourself with health care laws surrounding
genetics (GINA, state laws surrounding NBS)• Take a look at 23andme website (good intro to• direct to consumer testing)• National Society of Genetic Counselors (NSGC)• Genetic Task Force of Illinois (GTFI)
SUMMARY
11/13/2017 39
• Our understanding of molecular genetics has rapidly increased and molecular genetics is becoming an increasingly relevant and integral part of reproductive medicine
• Genetic counseling may be the right career for you!
11/13/2017 40
Thanks for attending!
Brook Croke, M.S., M.P.H.Genetic Counselor, CooperGenomics
UIUC MCB Workshop SeriesNovember 13, 2017
Pioneers and Global Leaders Advancing Reproductive Genetics
© 2017 CooperSurgical, Inc. All Rights Reserved.