Table 1

Table 1. Summary of key hippocampal values in BXD recombinant inbred strain
	Case		Bilateral Weight Hippocampus	Bilateral Weight			Granule Cells		Granule Cells		Brain Weight		D1 Mit145 89 cM**		D1 Mit218 67 cM**		D5 Mit197 36 cM**		D5 Mit352 20 cM**
Strain	N		(mg) ± SE Corrected*	(mg) ¶			per mm³ x10³		n x10³‡		(mg) ‡‡		Geno- type		Geno- type		Geno- type		Geno- type
BXD1	3	27.5 ± 0.3			27.6	1040		1067		433		B		B		B		B
BXD2	3	25.8 ± 0.4			24.9	849		639		419		B		B		D		D
BXD5	6	25.2 ± 0.6			29.9	859		835		544		D		D		D		D
BXD6	11	28.3 ± 0.4			26.7	-		-		386		B		D		B		B
BXD8	6	26.5 ± 0.7			28.7	974		1155		477		B		B		B		B
BXD9	10	25.1 ± 0.4			25.7	936		708		448		D		B		D		B
BXD11	11	25.9 ± 0.1			25.2	756		793		415		D		D		B		D
BXD12	5	25.7 ± 0.5			26.7	985		887		453		B		B		D		B
BXD13	10	25.5 ± 0.2			23.5	850		864		384		D		D		B		B
BXD14	12	26.7 ± 0.3			26.4	880		1019		412		B		B		B		B
BXD15	6	25.8 ± 0.6			26.2	907		766		447		D		D		B		B
BXD16	10	27.1 ± 0.4			28.1	892		-		455		B		B		D		D
BXD18	10	25.8 ± 0.5			26.0	1010		800		435		B		B		B		B
BXD19	10	28.1 ± 0.3			28.0	954		1002		436		B		B		D		D
BXD20	7	26.0 ± 0.8			24.3	921		709		399		B		D		D		D
BXD21	11	25.9 ± 0.2			25.6	-		-		429		B		B		D		B
BXD22	5	24.0 ± 0.2			24.5	928		960		441		D		B		D		D
BXD23	5	24.7 ± 0.6			24.5	828		725		435		D		D		D		B
BXD24	8	23.8 ± 0.6			21.6	1053		766		388		D		D		D		D
BXD25	9	24.8 ± 0.3			23.7	782		966		412		D		B		B		B
BXD27	10	25.6 ± 0.4			22.9	837		684		373		D		D		B		B
BXD28	10	24.9 ± 0.2			24.1	932		742		415		D		D		D		D
BXD29	6	24.8 ± 0.3			23.3	900		645		403		D		D		B		B
BXD30	5	23.9 ± 0.2			21.3	905		734		367		D		D		D		D
BXD31	5	24.7 ± 0.2			23.7	860		700		409		B		B		D		D
BXD32	10	23.5 ± 0.5			24.1	970		809		444		D		D		D		D
BXD33	5	27.4 ± 0.2			26.7	822		760		427		D		D		B		B
BXD34	5	25.0 ± 0.1			24.4	850		533		420		D		D		D		D
BXD35	6	27.3 ± 0.5			26.4	897		772		413		B		D		B		B
BXD36	5	27.6 ± 0.2			26.4	837		664		405		B		B		D		D
BXD37	3	25.1 ± 0.3			23.6	-		-		411		D		D		D		B
BXD38	9	28.5 ± 0.3			28.3	793		718		418		B		B		B		B
BXD39	5	26.7 ± 0.3			25.3	793		776		405		D		D		D		B
BXD40	7	30.8 ± 0.3			30.8	853		995		438		B		B		B		B
BXD42	5	27.5 ± 0.2			28.2	748		794		443		B		B		D		D
C57BL/6J	13	27.4 ± 0.3			28.4	857		886‡		496		B		B		B		B
DBA/2J	24	26.4 ± 0.3			23.0	871		697‡		415		D		D		D		D
Average	8	26.1 ± 0.4			25.7	889		806		426
Bilateral hippocampal weight after correction by multiple regression for differences in logarithm of age, sex, body weight and brain minus hippocampal weight. These values were used for QTL mapping. All cases were adjusted to that of 75-day-old 22g female mice with a brain weight of 420 mg. ¶ Bilateral hippocampal weight with adjustment only for age and sex (no adjustment for brain weight). Data are values expected of 75-day-old female mice. These values are very close (within 5%) of values of the original uncorrected data. ‡ Bilateral (summed) estimates of granule cells in the dentate gyrus averaged across 5 cases in each strain. The SE of each estimate is typically under 30,000 cells. For the two parental strains, C57BL/6J and DBA/2, we have used two different sampling procedures one of which is described in Methods and Material. Estimates for the parental strains listed here rely on the same method used to count the BXD strains (10 samples from 5 cases). The difference between protocols is under 10%. ‡‡Brain weight is the average of the particular sample used for hippocampal dissection. The average number of cases used to estimate granule cell density and number is five per strain. *MIT microsatellite marker genotypes. The four columns of genotypes are taken from public databases generated and maintained by the Informatics Center for Mouse Neurogenetics (www.nervenet.org/MMfiles/MMlist.html). B alleles are inherited from C57BL/6J whereas D alleles are inherited from DBA/2J. Positions in centimorgans (cM) are taken from the Mouse Genome Database (www.informatics.jax.org/searches/marker_form.shtml).

D1

Mit145

D1

Mit218

D5

Mit197

D5

Mit352