PGT-M

Preimplantation Genetic Testing for Monogenic Disorders

14 business days (after probe design phase)Illumina platform NGS + Linkage AnalysisTrophectoderm biopsy + parental/family DNA samples for probe development

What is this test?

PGT-M screens IVF embryos for a specific single-gene (monogenic) disorder that runs in your family — such as cystic fibrosis, sickle cell disease, thalassemia, spinal muscular atrophy, or Huntington disease. Unlike PGT-A which looks at whole chromosomes, PGT-M targets the exact genetic variant identified in the parents, allowing you to select embryos that are unaffected by the condition before transfer. This test requires a customized probe design phase specific to your family's mutation.

Key Benefits

Prevent Specific Genetic Disease

Select embryos that are free of the specific genetic condition in your family, preventing transmission to the next generation.

Custom-Designed for Your Family

Unlike one-size-fits-all panels, PGT-M is a bespoke test designed specifically for your family's unique mutation and genetic background.

Carrier Detection

Identifies which embryos are carriers versus completely unaffected, giving you and your genetic counselor complete information for decision-making.

Combines with PGT-A

PGT-M can be performed alongside PGT-A in the same biopsy, screening for both the single-gene condition and chromosomal abnormalities simultaneously.

How It Works

Genetic Counseling & Case Review

Our genetics team reviews the family's genetic testing reports, confirms the specific mutation(s), and determines the inheritance pattern. Both partners provide DNA samples.

Custom Probe Design (4-6 weeks)

We develop a family-specific testing strategy using informative SNP markers flanking the mutation site. This requires DNA from both parents and, when available, affected or unaffected family members to establish linkage.

IVF & Embryo Biopsy

Once the probe is validated, your fertility clinic proceeds with IVF. Trophectoderm biopsy is performed on Day 5/6 blastocysts and cells are sent to our laboratory.

Targeted Sequencing & Linkage Analysis

Each embryo is tested for the specific familial mutation using direct variant detection combined with linkage analysis of flanking markers to confirm accuracy and detect recombination events.

Results & Embryo Classification

Embryos are classified as unaffected, affected, or carrier. Results include PGT-A (aneuploidy screening) when requested. Genetic counseling is available to review results and plan transfer.

Who should consider this test?

Couples where both partners are carriers of the same autosomal recessive condition (e.g., cystic fibrosis, thalassemia, SMA)
Couples where one partner carries an autosomal dominant condition (e.g., Huntington disease, BRCA mutations)
Carriers of X-linked conditions (e.g., Duchenne muscular dystrophy, hemophilia)
Couples who have previously had an affected child and want to prevent recurrence
Couples identified as at-risk through carrier screening or family history

Accuracy & Clinical Evidence

Test Accuracy

Over 98% accuracy for targeted single-gene variant detection when combined with linkage analysis using informative SNP markers flanking the mutation.

PGT-M has been used clinically for over two decades with well-established accuracy. Studies demonstrate diagnostic accuracy exceeding 98% when using combined direct mutation detection and linkage analysis with informative flanking markers. The technology has prevented transmission of hundreds of known monogenic conditions worldwide.

For Healthcare Providers

PGT-M is performed using a combination of targeted mutation detection and haplotype-based linkage analysis with informative SNP markers flanking the gene of interest. The probe design phase (4-6 weeks) requires DNA from both partners and ideally an affected or known-status family member to establish phase. Testing uses whole genome amplification followed by targeted sequencing on the Illumina platform. Allele dropout (ADO) is mitigated by redundant linkage markers. Combined PGT-A is available as an add-on. All results are reported per PGDIS guidelines.

Important Limitations

Requires a 4-6 week probe design phase before embryo testing can begin — plan accordingly with your IVF timeline.
Family DNA samples (ideally from an affected family member) significantly improve probe reliability — limited family samples may reduce informative markers available.
Allele dropout (ADO) is an inherent risk in single-cell testing — linkage analysis minimizes but does not eliminate this risk.
PGT-M does not screen for all genetic conditions — only the specific mutation(s) designated in the probe design.
Carrier embryos are identified but are healthy; the decision to transfer carriers involves genetic counseling discussion.