Table 4 Comparison of UDN-driven investigations at the clinical sites to standard clinical genetics practice.

From: Clinical sites of the Undiagnosed Diseases Network: unique contributions to genomic medicine and science

Characteristics/investigations

UDN

Clinical practice

Participant characteristics

Refractory to multiple prior clinical and laboratory evaluations, and often ES negative

More likely to not have ES, may or may not have failed prior clinical evaluations

Time spent on pre-, post-, and face-to-face activities

Face-to-face time represents a minority of time required for clinical and research activities (record review, literature review, phenotyping, bioinformatics, variant curation, RNASeq, collaborative science, integration of all data)

Limited by clinical demands and financial constraints to a few hours for all activities

Equity in access:

•Geographic access

•Financial considerations

Accessible to all in USA and internationallya

All eligible irrespective of finances

Regional access more likelya Financial considerations likely factor

Complementation/supplementation of prior clinical data

Personalized, temporally concentrated, comprehensive N-of-1 clinical consultations/laboratory tests/imaging/procedures

• Fills in phenotypic gaps and generates additional clinical information

• Leads to clinical diagnoses, diagnoses on targeted testing and contributes to genomic diagnoses

Variable, less likely to be temporally concentrated and comprehensive

Time and financially constrained in filling in gaps and obtaining new information

Innovative analyses of genomic data

Straightforward diagnoses on UDN sequencing

• ES/GS (35% diagnostic yield)

Research reanalysis of pre-UDN raw data from nondiagnostic ES (diagnostic yield of 43%)

• Multiple other approaches to resolving prior ES negatives

Dual analysis of UDN-generated genomic data by UDN core lab and clinical sites

• Clinical site analysis led to additional genomic diagnoses (8%)

Manual curation of research variants generated by clinical site and core lab genomic analysis

RNASeq: Internal collaborations led to generation and analyses of RNASeq (contributed to diagnoses in 15%)

New disease gene identification

• 8% of genomic diagnoses were novel disease–gene associations

• Can be pursued with internal collaborations

Straightforward diagnoses on clinical ES (diagnostic yield 25–30% in literature); GS less widely available

Standard reanalysis of negative ES with same pipeline (diagnosis yield of 6.5% at Duke, Stanford and Vanderbilt), 10–15% in literature

• Limited further options to resolve ES negatives

Dual analysis unavailable due to lack of bioinformatics in clinics

Clinicians do not receive research variants from clinical labs for curation

Limited availability of RNASeq, with the clinical laboratory determining access

New disease gene identification

• Time and resource constrained

  1. ES exome sequencing, GS genome sequencing, UDN Undiagnosed Diseases Network.
  2. aSee Fig. S2 for detailed travel data.