What is the difference between single phasing and duo/trio phasing?

Phasing services differ in accuracy and data requirements:

Single (Statistical) Phasing:

What it uses:

• Only your DNA file
• Statistical algorithms
• Large reference populations
• Population linkage patterns

How it works:

• Analyzes patterns in your DNA
• Compares to known haplotype blocks
• Predicts most likely parental assignments
• Uses probability models

Accuracy: 85-95%

Best for:

• When parent DNA is unavailable
• General ancestry analysis
• Basic genealogy work
• Budget-friendly option

Duo Phasing:

What it uses:

• Your DNA file
• ONE parent's DNA file
• Direct comparison

How it works:

• Directly compares your DNA to parent's DNA
• Identifies which variants came from that parent
• Infers remaining variants came from other parent
• Minimal statistical guessing

Accuracy: 97-99%

Best for:

• One parent available for testing
• Deceased or unavailable parent
• High-accuracy needs

Trio Phasing:

What it uses:

• Your DNA file
• Mother's DNA file
• Father's DNA file
• Complete direct comparison

How it works:

• Direct comparison to both parents
• Identifies exact inheritance from each
• Nearly eliminates statistical uncertainty
• Gold standard for phasing

Accuracy: 99%+

Best for:

• Both parents available
• Maximum accuracy needed
• Research or medical purposes
• Genealogy preservation

Comparison Table:

Which Should You Choose?

• Single: Parents unavailable, general use
• Duo: One parent available, good balance
• Trio: Both parents available, best results