Exhibit 21.1

Quest Diagnostics Incorporated (DE)
(Incorporated on December 12, 1990 in Delaware; FEIN No. 16-1387862)

Subsidiaries and Joint Ventures

100% Quest Diagnostics Holdings Incorporated (f/k/a SBCL, Inc.) (DE)
	100%	Quest Diagnostics Clinical Laboratories, Inc. (f/k/a SmithKline Beecham Clinical
		Laboratories, Inc.) (DE)
		(33-l/3%) Compunet Clinical Laboratories (OH)
		(44%)		Mid America Clinical Laboratories (IN)
		(51%)		Diagnostic Laboratory of Oklahoma LLC (OK)
100%	Quest Diagnostics Nichols Institute (f/k/a Quest Diagnostics Incorporated) (CA)
100%	Quest Diagnostics Incorporated (MD)
		100%	Diagnostic Reference Services Inc. (MD)
			100%      Pathology Building Partnership (MD) (gen. ptnrshp.)
100%	Quest Diagnostics Incorporated (MI)
100%	Quest Diagnostics Investments Incorporated (DE)
	100% Quest Diagnostics Finance Incorporated (DE)
100%	Quest Diagnostics LLC (IL)
100%	Quest Diagnostics LLC (MA)
100%	Quest Diagnostics LLC (CT)
100%	Unilab Corporation (DE)
	100% FNA Clinics of America, Inc. (f/k/a Unilab Acquisition Corporation) (DE)
100%	Quest Diagnostics of Pennsylvania Inc. (DE)
	51%	Quest Diagnostics Venture LLC (PA)
	53.5%	Associated Clinical Laboratories (PA) (gen. ptnrshp.)
		100% North Coast General Services, Inc. (PA)
100%	Quest Diagnostics of Puerto Rico, Inc. (PR)
100%	Quest Diagnostics Receivables Inc. (DE)
100 %	Quest Diagnostics Ventures LLC (DE)
100%	DPD Holdings, Inc. (DE)
	100%	MetWest Inc. (DE)
		100% Diagnostic Path Lab, Inc. (TX)
		100% Quest Diagnostics Provider Network, LLC (CO)
		49%   Sonora Quest Laboratories LLC (AZ)
100%	American Medical Laboratories, Incorporated (DE)
	100%	AML Inc. (DE)
		100% Quest Diagnostics Nichols Institute, Inc. (f/k/a Medical Laboratories Corporation)
		(VA)

		100% Quest Diagnostics Incorporated (NV)
		100%      APL Properties Limited Liability Company (NV)
100%	Enterix Inc. (DE)
	100%	Enterix (Australia) Pty Limited (Australia)
		100% Enterix Pty Limited (Australia)
		100%   Enterix UK Limited (UK)
100%	Focus Technologies Holding Company (DE)
	100%	Focus Diagnostics, Inc. (DE)
100%	HemoCue, Inc. (CA)
100%	QDI Acquisition AB (Sweden)
`	100%	POCT Holding AB (Sweden)
		100% HemoCue Holding AB (Sweden)
		100% HemoCue AB (Sweden)
		100% HemoCue Oy (Finland)
		100% HemoCue GmbH (Germany)
		99.7% HemoCue AG (Switzerland)
		100% Biotest Medizintechnik GmbH (Germany)
		100% HemoCue Diagnostics B.V. (The Netherlands)
		100% HC Diagnostics, Limited (UK)
100%	Lab Portal, Inc. (DE)
100%	LabOne, Inc. (MO)
	100% ExamOne World Wide, Inc. (PA)
		100% ExamOne World Wide of NJ, Inc. (NJ)
	100%	Systematic Business Services, Inc. (MO)
		100% Scan Tech Solutions, LLC (MO)
	100%	LabOne, L.L.C. (KS)
	100%	Central Plains Holdings, Inc. (KS)
		100% Central Plains Laboratories, LLC (KS)
	100%	Lab One Canada, Inc. (Ontario)
		100% ExamOne Canada, Inc. (Ontario)
		100% Rapid-Med Plus Franchise Corporation (Ontario)
	100%	LabOne of Ohio, Inc. (DE)
	100%	Osborn Group Inc. (DE)
		100% Intellisys, Inc. (GA)
100%	Lifepoint Medical Corporation (DE)
	100%	C&S Clinical Laboratory, Inc. (d/b/a Clinical Diagnostic Services) (NJ)
100%	MedPlus, Inc. (OH)
	100%	Worktiviti, Inc. (fka Universal Document Management Systems, Inc.) (OH)
	100%	Valcor Associates Inc. (PA)
100%	Nichols Institute Diagnostics (CA)
100%	Nichols Institute Diagnostics Limited (UK)
100%	Nichols Institute Diagnostics Trading AG (Switzerland)
100%	Nichols Institute Diagnostika GmbH (Germany)
	100%	Nichols Institute Diagnostika GmbH (Austria)
100%	Nichols Institute International Holding B.V. (Netherlands)

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	100%	Nichols Institute Diagnostics B.V. (Netherlands)
	100%	Nichols Institute Diagnostics SARL (France)
100%	Nomad Massachusetts, Inc. (MA)
	100%	Quest Diagnostics Mexico, S.A. de C.V. (f/k/a Laboratorios Clinicos de Mexico, S.A. de
		C.V. (Mexico)
	100%	Laboratorio de Analisis Biomedicos, S.A. (Mexico)
100%	Quest Diagnostics do Brasil Ltda. (Brazil)
100%	Quest Diagnostics India Private Limited (India)
100%	Quest Diagnostics Limited (UK)
	100%	The Pathology Partnership plc (UK)
19.9%	Clinical Genomics Pty Ltd. (Australia)

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