Table 4.

Endophenotype 4. Volumetric Abnormalities of the sgACC in MDD.

Study	Sample	Age	Method	Clinical Status at Testing	Medication Status	Findings
(Drevets et al., 1997a)	10 MDD 21 HC	39±7.3 34±8.2	1mm ROI	Depressed	Unmedicated 4+ weeks	Decreased volume of L sgACC in MDD group
(Botteron et al., 2002)	30 MDD 8HC	20.2±1.6	1mm ROI	Depressed	Less than 10% of MDD sample on medication.	Decreased volume of L sgACC in MDD
(Kegeles et al., 2003)	19 (14 MDD, 5 BD) 10 HC	36±11 39±19	1.5mm ROI	Depressed	BZ discontinued 24 hours before study in 12 cases. 7 subjects on BZ. Patients free of other medication for 2+ weeks.	NS
(Hastings et al., 2004)	18 MDD 18 HC	38.9±11.4 34.8±13.6	1.5mm ROI	Depressed	Unmedicated	Volume reduction in L sgACC in males only
(Coryell et al., 2005)	10 MDD 10 SCZ 10 HC	22±4.9 22±6.0	1mm ROI	Depressed	NR	Volume reductions in L posterior sgACC but not anterior sgACC in MDD with psychotic features
(Boes et al., 2008)	31 HC – no family history 28 HC - + family history	12.0±2.72 12.1±2.13	1.5mm ROI	Mixed	NR	In boys (but not girls) with subclinical depression smaller L perigenual (sgACC + pgACC) volumes.
(Chen et al., 2007a)	17 MDD	44.1±8.36	3mm VBM	Depressed	Scanned before and after treatment with fluoxetine. Patients unmedicated 4+ weeks before study.	Greater GM volume of pgACC (0, 41, 2) and sgACC (0, −31, −2) associated with faster improvement to fluoxetine
(Tang et al., 2007)	14 MDD 13 HC	29.5±6.84 29.5±6.86	1.6mm ROI	Depressed	Naive	Decreased volume of sgACC in MDD at x=2; y=30; z= −2
(Yucel et al., 2008)	65 MDD 93 HC	28.8±10.3 28.4±10.7	1.2mm ROI	Depressed	Short-term treatment with various AD	Decreased volume of BA25 in MDD Only MDD patients with medication exposure had smaller BA24 volume.

Note: AD=antidepressant medication; BZ=benzodiazepenes; HC=healthy control; MDD=major depressive disorder; NR=not reported; NS=not significant; pgACC=perigenual anterior cingulated cortex; sgACC=subgenual anterior cingulated cortex; ROI=region of interest; VBM=voxel-based morphometry.