What Is PGT? 4 Main Types of Preimplantation Genetic Testing

Before implantation in IVF, embryos can undergo genetic testing—this is known as PGT (Preimplantation Genetic Testing). There are four common types:

Type	Full Name	Family History Required?	What It Screens	Who It’s For
PGT-A	Aneuploidy Screening	❌ No	Checks for abnormal chromosome numbers (e.g., Down syndrome)	Women over 35, recurrent miscarriage, repeated failed transfers
PGT-M	Monogenic/Single-Gene Testing	✅ Yes	Inherited single-gene disorders (e.g., thalassemia, CF)	Carriers of known genetic disorders
PGT-SR	Structural Rearrangement Screening	✅ Usually	Chromosomal translocations, inversions, duplications	People with known chromosome rearrangements
PGT-P	Polygenic Risk Scoring	❌ No	Estimates risk of complex traits: diabetes, heart disease, cognitive potential	Families seeking broader health or trait screening

---

Can PGT-P Really Predict Intelligence?

This is the most common (and controversial) question.

PGT-P can assess genetic predisposition related to cognitive ability, but it cannot directly measure or “select” intelligence.

PGT-P is based on polygenic risk scoring (PRS). It analyzes thousands of genetic variants statistically linked to certain complex traits—like IQ—based on massive population-level genome studies.

But here’s the truth:

• Genetic factors explain only 5–10% of IQ variation in current models

• Selecting the embryo with the highest PRS score for cognition may only yield an average IQ difference of 2–3 points

• The number of embryos per IVF cycle is limited, so the practical impact is small

• In other words, PGT-P does not “choose smart babies”—it may only slightly tilt the odds toward a genetic profile loosely associated with cognitive ability.

---

What About Emotional Intelligence (EQ)? Can PGT-P Screen for That?

No. Currently, there is no scientific basis or reliable genetic model for predicting or selecting emotional intelligence.

Traits like empathy, self-awareness, emotional regulation, and social skills are heavily influenced by environment, upbringing, and education—not clearly by genetics.

Any claims that PGT-P can screen for EQ or personality are unsupported by science and should be viewed skeptically.

---

Does PGT-P Require a Family History of Genetic Conditions?

No, it does not.

Unlike PGT-M, which is used to avoid passing on known inherited disorders, PGT-P is a non-targeted screening tool. It can be used by any couple going through IVF, even if they have no genetic disease in their family.

It is typically considered by:

• Couples with multiple embryos who want to consider long-term health risk profiles

• Families with history of chronic conditions (e.g., diabetes, heart disease, Alzheimer’s)

• Parents who are interested in traits like cognitive ability or mental health predisposition

---

Limitations & Ethical Concerns of PGT-P

While the science behind PGT-P is rapidly evolving, it also comes with important limitations and ethical debates.

Scientific Limits

• PRS models are mainly based on European-ancestry populations; their accuracy in other ethnic groups is uncertain

• Trait predictions are probabilistic—not deterministic

• Small genetic differences may not translate into meaningful real-world outcomes

Ethical Questions

• Will this lead to new forms of inequality (“designer baby” access for the wealthy)?

• Does embryo selection place unfair expectations on the child?

• Where is the line between health screening and enhancement?

---

 Final Takeaway: PGT-P Is a Tool, Not a Guarantee

What You Should Know	Explanation
✅ No family history needed	Available for all IVF patients
�� Slight influence on cognitive genetic profile	Average IQ benefit very small (2–3 points at most)
❌ Cannot screen for EQ or personality	No scientific model currently exists
⚠️ Still experimental, not diagnostic	Should be used with caution and professional guidance