Podcast Summary: 5 Questions with Dr. Xiao Peng

Podcast: Blood, Sweat and Smears – A Machaon Diagnostics Podcast
Host: Bjorn (filling in for Dr. Brad Lewis)
Guest: Dr. Xiao Peng, Assistant Professor, Division of Genetics, Department of Pediatrics, Children’s Hospital at Montefiore
Date: October 4, 2024

Main Theme

This episode spotlights Dr. Xiao Peng, a clinical geneticist and co-director of the New York Center for Rare Diseases at Montefiore. Through five insightful questions (plus a bonus), Dr. Peng delves into her mission to integrate clinical and molecular medicine for rare disease patients, her passion for biomarker discovery, her unique contributions as a geneticist, and the parallels she draws between her work and her love of wine.

Key Discussion Points & Insights

1. What are you building at Montefiore?

(01:21–04:56)

• Integrated, End-to-End Rare Disease Care:
  Dr. Peng describes an ambitious vision to offer rare disease patients full-spectrum care, combining clinical expertise, advanced molecular diagnostics, and tailored therapies. Their focus is on seamless, patient-centered service.

  “We’re really trying to reconcile clinical with molecular medicine and also build end-to-end care for our patients... from the initial evaluation through to tailored therapies.” — Dr. Xiao Peng (01:27)

• Overcoming Barriers:
  She highlights bureaucratic and logistical obstacles faced by underserved communities, such as those in the Bronx, and stresses the importance of equitable access to cutting-edge care.

  “There’s a very, very strong burden—as Bruce McEwen would call allostatic load—that already contributes to patients who have chronic rare disease.” (02:21)

• Diverse Patient Insights:
  The Bronx’s diversity provides unique perspectives and learning opportunities, underscoring the value of comprehensive data and representation.

• Innovative Diagnostics:
  Dr. Peng emphasizes the use of advanced tools (e.g., long-read sequencing, optical genome mapping), cost-effective tailored testing, and pangenome assemblies to better capture genetic diversity.

  “We’re hoping to do some more de novo and pangenome assemblies, really to capture all of that missing diversity in our reference databases.” (04:10)

• Functional Validation:
  They’re building capacity to functionally validate genetic variants, moving beyond identification to mechanism and treatment.

2. If your work was a wine, how would you describe it?

(05:10–07:46)

• Complexity and Discovery:
  Dr. Peng likens her work to wines from the islands of Sicily, Corsica, and Crete: layered, surprising, and resistant to simplistic descriptions.

  “The first bottle of Nerello Mascalese, Nerello Cappuccio I had from the area around Mount Etna was mind blowing... at times Bordeaux, sometimes Burgundy, sometimes Sangiovese, but ultimately it’s its own thing.” (05:36)

• Analogy to Patient Care:
  Just as rare wines require exploration and new vocabulary to describe, so too do rare undiagnosed cases require humility and a spirit of ongoing discovery.

  “There’s many, many ongoing layers of exploration and wonder. You just feel so humbled at the generosity of the patients and what they teach us.” (07:18)

3. Favorite Biomarker?

(07:57–09:56)

• CD169 Flow on Monocytes:
  Dr. Peng names CD169 flow cytometry as a “game changer” for detecting Type I interferon activation, crucial in a range of rare autoimmune and inflammatory diseases.

  “The ability to perform CD169 flow on monocytes as a surrogate readout for type 1 interferon activation... has been an incredible game changer.” (08:05)

• Clinical Impact:
  This assay enables rapid, clinically actionable screening (via 1cc of blood) for pathways connected to conditions like lupus, facilitating targeted therapies (e.g., JAK inhibitors).

• Historical Challenges:
  She reflects on past difficulty accessing this information, noting the importance of recent advances and innovations from laboratory leaders.

4. Most Enjoyable Part of Your Work

(10:02–11:45)

• Patient Interaction & Communication:
  Dr. Peng finds deep fulfillment in connecting with patients, breaking down complex science, and building trusting relationships, despite once believing her introverted background would be a barrier.

  “Being able to feel that a patient feels supported from you, feels like their concerns are validated... that’s been one of the most rewarding parts of my job.” (10:54)

• The Human Side:
  These meaningful conversations and shared “aha moments” with patients are the highlight of her career.

5. Role and Timing as a Clinical Geneticist

(12:06–16:06)

• Versatility & Evolution of the Field:
  Dr. Peng explains her varied and often unique role in the clinical workflow, particularly for genetically driven hematologic and immune diseases—a field historically overlooked for genetic input.

  “The involvement of clinical geneticists in genetically driven blood and immune disease has been probably much, much patchier... I can probably count on one hand the number of other genetics colleagues I know who are involved in this area.” (12:31)

• Changing Landscape:
  Improvements in first-line genomic and immune function testing are bringing geneticists into earlier diagnostic phases, including in adult populations.

  “That is really, really changing now, certainly with the advent of a lot more upfront first line next generation sequencing...” (13:36)

• Multifaceted Contributions:
  Dr. Peng’s involvement ranges from frontline diagnostics to long-term counseling and team coordination: sometimes therapist, sometimes “quarterback,” sometimes technical expert.

  “With some patients, I’m really the therapist and the genetic counselor more than actively prescribing medications... with other families, I’m more of the quarterback... and in other situations, really on the front line.” (15:15)

Bonus: Dr. Peng’s Recommendation

(16:18–18:14)

• Champagne as a Travel Companion:
  For solo travelers and wine enthusiasts, Dr. Peng recommends ordering a bottle of champagne with dinner. She highlights its versatility throughout a meal and suggests leaving what you don’t finish for the restaurant staff.

  “Champagne... is actually an incredible wine to pair with food. As it develops in your glass, you get more layers, more complexity... If I had to pick a bottle for a 13-course meal, I would pick a bottle of champagne.” (17:00)

• Travel Well:
  She encourages enjoyment and cultural exploration, “Travel well, buy yourself a bottle of champagne, and enjoy your dinner.” (18:10)

Memorable Quotes

• “There’s a very, very strong burden—as Bruce McEwen would call allostatic load—that already contributes to patients who have chronic rare disease.” — Dr. Peng [02:21]
• “The first bottle of Nerello Mascalese…I had from the area around Mount Etna was mind-blowing…It wasn’t actually any of those things. It had its own kind of character.” — Dr. Peng [05:36]
• “The ability to perform CD169 flow on monocytes as a surrogate readout for type 1 interferon activation…has been an incredible game changer.” — Dr. Peng [08:05]
• “Being able to feel that a patient feels supported and validated…that’s been one of the most rewarding parts of my job.” — Dr. Peng [10:54]
• “I can probably count on one hand the number of other genetics colleagues I know who are involved in the care of patients with genetically driven blood immune disease. You know, we're a very small community to begin with.” — Dr. Peng [12:40]
• “If I had to pick a bottle for a 13-course meal, I would pick a bottle of champagne…Start off tight and zippy, it gets more complex…and the staff can finish what you don’t.” — Dr. Peng [17:00]

Notable Timestamps

• 01:21: Dr. Peng describes her vision for the NY Center for Rare Diseases
• 04:10: Advanced genomics and pangenome work
• 05:36: Wine analogy—comparing work with rare wines
• 08:05: Favorite biomarker—CD169 flow cytometry for interferon activation
• 10:54: The joy of patient communication and trust
• 12:36–16:06: How and when geneticists are involved; evolving role
• 17:00: Champagne recommendation for solo travel dining

Tone and Takeaways

Dr. Peng comes across as thoughtful, passionate, and humble—with a knack for drawing vivid analogies between worlds as different as genetics and wine. Her commitment to both scientific rigor and human connection shapes a unique, empathetic approach to rare disease medicine.

The episode leaves listeners with an appreciation for both the complexity and the human dimension of rare disease care, and—with champagne as a metaphor for knowledge—reminds us to savor the nuance and surprise in every professional and personal journey.