This is our sixth installment in our Mock Genetic Counseling Session Series! In this episode, genetic counselor Charlotte Close and student Marcely Ventura perform a mock genetic counseling session. The session indication is an abnormal newborn screening result for cystic fibrosis.

This session was recorded in-person, providing a more dynamic and engaging learning experience therefore, we highly recommend watching it on YouTube to fully immerse yourself in the interaction.

We hope this series is helpful for prospective and current genetic counseling students, as well as the general public, by demystifying the genetic counseling process. Understanding how these sessions work can empower individuals and provide valuable educational insights into this critical healthcare service.

The Actors:

Marcely Ventura (she/her) is currently in her second and final year in the Human Genetics Program at Sarah Lawrence College training to be a genetic counselor. Ventura is a graduate of Hunter College with a B.A. in Human Biology. Ventura is the first recipient of the Lauren Ryan Genetic Counselor Access Memorial Award. This award celebrates Lauren Ryan’s legacy of advancing equity in genetic counseling and supports students from underrepresented communities. As a first-generation Hispanic college graduate, she is passionate about increasing access to genetic counseling for diverse communities and addressing health disparities. The premise of this mock case was part of her internship with DNA Today.

Charlotte Close, MS, CGC (she/her) is a certified genetic counselor in the Division of Clinical Genetics at Columbia University Irving Medical Center (CUIMC) and a member of the multidisciplinary cystic fibrosis care team at CUIMC. She is passionate about improving access to genetic counseling services and has worked with the Cystic Fibrosis Foundation, other cystic fibrosis genetic counselors, and cystic fibrosis care team members from across the country to achieve this goal through policy changes, service delivery innovation, and educational efforts. In addition to her clinical work, Close contributes to the Graduate Program in Genetic Counseling at Columbia University by supervising students, mentoring research projects, and serving as a course director. She also serves as a Director on the New York State Genetics Taskforce. She received her Bachelor of Science in Microbiology from the University of Michigan and her Master of Science in Human Genetics from Sarah Lawrence College.

Mock Session Information:

Session Indication: The patient is a 10 week old male with a positive newborn screen for cystic fibrosis who was referred to the genetics center by his pediatrician for further evaluation and discussion of genetic testing. The patient’s mother, Mary, is attending the appointment.

Case Details:

The patient is a 10 week old male with a positive newborn screen for cystic fibrosis who was referred to the genetics center by his pediatrician for further evaluation and discussion of genetic testing.

Patient Name: Liam Ventura

Parent Names: Mary and Sam Ventura

Medical History:

Pregnancy:
- Uncomplicated
- Full term (39 wks) via NSVD
- No exposures or complications reported
- Normal prenatal ultrasounds
Newborn Screening:
- Elevated immunoreactive trypsinogen (IRT)
- Two CFTR variants identified on screening panel
Development: Appropriate for age
Growth: Slightly below weight percentile
Symptoms: Mild cough, parents believe it’s due to the change of weather
Specialists Seen: Pediatrician only so far
Medications/Treatments: None currently
Therapies: None currently

Family History:

Ancestry: Dad- Irish Mom- Af. American
No consanguinity, birth defects, or known genetic conditions
No history of cystic fibrosis or early infant deaths
One paternal cousin with male infertility

Prior Carrier Results:

Dad- F508del Carrier
Mom- Negative …. After first visit with Multidisciplinary team following variant is identified: c.1675G>A p.A559T

Pediatric Mock Session Outline

Contracting

Greetings and introductions
Reason for referral to genetic counseling (positive newborn screening for CF)
Overview of session and what will be discussed: “I’m going to ask a lot of questions about when Liam was in your belly, up until now, as well as medical and family history questions just to make sure we have a full picture and aren’t missing anything. After that Dr.X will come in and do a physical/sweat test on Liam and we can talk about genetic testing options, how does that sound/any questions before we get started?”

Address patient questions or concerns such as:
- “What does this mean for our baby?”
- “Does this mean he has cystic fibrosis?”
- “Could this happen again in another pregnancy?”
- “Did we do something to cause this?”

Medical Intake

Review pregnancy and delivery history
Review newborn history
Review of systems with focus on:
- Respiratory symptoms
- Digestive symptoms and growth patterns
- Frequency of infections
Developmental milestones and any delays noted by parents
Medications, supplements, or current therapies

Family History

Construct a three-generation pedigree
Ask about consanguinity, early childhood deaths, chronic respiratory or digestive issues, and male infertility
Determine if any relatives have known carrier status for CF or other genetic conditions

Patient Education:

Overview of Genetics

Explanation of autosomal recessive inheritance
Each parent is likely a carrier of one CFTR gene variant
With each pregnancy:
- 25% chance for a child with CF
- 50% chance to be a carrier
- 25% chance to be unaffected and not a carrier

Cystic Fibrosis Overview

Genetic condition that can affect the lungs and digestive system
Caused by variants in the CFTR gene that affect how mucus and other secretions function
Range of possible symptoms from mild to more significant depending on variants involved (explain variable expressivity)

Genetic Testing Discussion

Both parents previously had carrier testing done, dad came back with a variant and mom did not.
Testing options:
- CFTR gene sequencing and deletion/duplication analysis for mom: c.1675G>A p.A559T variant is found afterwards
Sample collection: Blood or saliva
Results:
- Positive: Confirms CF diagnosis

Testing Process

Turnaround time: 2–4 weeks
Informed consent and shared decision-making

Recommendations and Next Steps

Proceed with diagnostic testing for Liam
Offer CFTR gene sequencing to parents
Coordinate follow-up once results are available, will call once results are available
Provide educational resources on CF and genetic testing
Discuss implications for future pregnancies

Relevant Cystic Fibrosis Genetic DNA Today Episodes:

#147 CF Series: Bijal Trivedi on "Breath From Salt"

#148 CF Series: Shuling Guo on Pharmaceuticals

#149 CF Series: Boomer Esiason’s Son Gunnar on Patient Advocacy

Previous installments of our Mock Genetic Counseling Session series:

Episode #311: Cancer Session for Breast and Prostate Cancer Family History

Episode #317: Prenatal Session for Advanced Maternal Age

Episode #331: Pediatric Session for Autism

Episode #351: Cardio Session for Sudden Death of A Family Member

Episode #368: Prenatal Session for Increased Nuchal Transluency

Disclaimer:

Please note that the information provided in this mock genetic counseling session is intended strictly for educational purposes and should not be used for personal medical decision-making. If you have questions or concerns about your health, we encourage you to consult directly with a certified genetic counselor who can provide tailored medical recommendations. If you are in the United States, you can find a genetic counselor near you by visiting FindAGeneticCounselor.com. Stay tuned for an international genetic provider directory.

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