Brief Description

Mycobacterium  tuberculosis (MTBC) genotyping refers to the laboratory procedures aimed at identifying specific genomic areas of isolates of M. tuberculosis.  The genotyping data may be used to identify false culture-positive tuberculoses (TB) suspects, confirm a suspected outbreak, identify a previously unsuspected outbreak, evaluate the effectiveness of contact investigations, and gain insight into TB transmission patterns and populations most vulnerable to recent transmission.

Laboratory Unit



Polymerase Chain Reaction (PCR)-based: Spacer oligonucleiotide typing (spoligotyping) analysis or Variable-Number Tandem Repeat of Mycobacterial Interspersed Repetitive Units (VNTR-MIRU) analysis

Gel electrophoresis:  IS6110-based restriction fragment length polymorphism (RFLP) analysis

Performed at the Michigan Department of Community Health TB Laboratory

Specimen Collection



Submit reference isolates of TB using a Category A mailer provided by the MSPHL in accordance with the Infectious Substance, Category A shipping guidelines.

Acceptable Specimen Type(s)

Only isolates of M. tuberculosis complex can be submitted for genotyping.

Test Request Form(s)

Possible Results

Spoligotype pattern containing a standardized 15 numerical code

VNTR-MIRU pattern containing a standardized 12 numerical code

National cluster designation

Unacceptable Conditions

Leaked during transport
No name on specimen
Mixed culture
Nonviable organism

Interfering Substances


Result Reported

Results are reported by the Missouri TB Control Program.



CPT Codes




Additional Information

19 CSR 20-20.080 Duties of Laboratories

"Isolates or specimens positive for [M. tuberculosis complex] must be submitted to the State Public Health Laboratory for epidemiological or confirmation purposes"