Table 1.

Genetic mouse models for differentiating the contributions of gonads and sex chromosome genes on sex differences

				Copy Number
Model (Strain) Dam x Sire	Genotype	Offspring common abbreviations	Gonads	NPX	NRY	Sry	PAR	Suggested uses:
Normal (various strains)
XX x XY	X Y	M	Testes	1	1	1	2	Establishing sex differences
	X X	F	Ovaries	2	0	0	2
FCG (various strains)
XX x XY− Sry	X Y− Sry	XYM	Testes	1	1	1	2	Determining whether sex differences are due to gonadal sex or sex chromosome complement
	X X Sry	XXM	Testes	2	0	1	2
	X Y−	XYF	Ovaries	1	1	0	2
	X X	XXF	Ovaries	2	0	0	2
Y* (C57BL/6J or MF1)
XX x XY*	X Y*	1XM	Testes	1 +	1	1	2 −	Determining if sex differences correlate with numbers of X- chromosomes and examining effects of Sts
	X XY*	2XM	Testes	2	1	1	2 −
	X Y*X	1XF	Ovaries	1 +	0	0	2
	X X	2XF	Ovaries	2	0	0	2
XY−Y*X Cross (MF1)
XX x XY− Y*X(Sry+)	XY−(Sry+)	XYM	Testes	1	1	1	2	Determining effects of the balance of sex chromosomes when two are present in either gonadal sex
	XY*X(Sry+)	X0+PAR M	Testes	1 +	0	1	2
	XX(Sry+)	XXM	Testes	2	0	1	2
	XY−	XYF	Ovaries	1	1	0	2
	XY*X	X0+PAR F	Ovaries	1 +	0	0	2
	XX	XXF	Ovaries	2	0	0	2
Y* Aneuploids (MF1 and/or C57)
XX x XY*	XY*	39, XY*O	Testes	1	1	1	2 −	When compared to normal, determining effects of aneuploidy, numbers of PAR and/or Sts and X chromosome origins
	X O	39, XO	Ovaries	1	0	0	1
XX x XPafY*	X maternal origin	39, XmO	Ovaries	1	0	0	1
40, ln(X)1H/XPaf x 40, XY	X paternal origin	39, XpO	Ovaries	1	0	0	1
XY*X x XY XX x XYY*X	X X Y	41, XXY	Testes	2	1	1	3
XYSry Aneuploids (MF1)
XXY− x XYSry	X Y	only male offspring shown	Testes	1	1	1	2	Comparing actions of the endogenous Sry versus the Sry transgene. Further analysis of effects of numbers and composition of sex chromosomes (including PAR)
	X Y Y−		Testes	1	2	1	3
	X Y Sry		Testes	1	1	2	2
	X Y Y− Sry		Testes	1	2	2	3
	X X Sry		Testes	2	0	1	2
	X X Y− Sry		Testes	2	1	1	3
Sex Chromosome Trisomy (MF1)
XXY− x XY−Sry	X X Y− Sry	XXY M	Testes	2	1	1	3	Examining effects of the balance of sex chromosomes when three are present in either gonadal sex
	X Y− Y− Sry	XYY M	Testes	1	2	1	3
	X X Y−	XXY F	Ovaries	2	1	0	3
	X Y− Y−	XYY F	Ovaries	1	2	0	3
	FCG offspring
POS (C57BL/6J)
XX x XYPOSI	X Y-poschiavinus	XYPOSI	Ovotestes	1	1	1	2	Determining effects of sex chromosome complement in gonadal females
	X Y-poschiavinus	XYPOSF	Ovaries	1	1	1a	2
	XX	XXF	Ovaries	2	0	0	2
Odsex (FVB)
XX x XYMOds	X Y Sox9-overexp.	XYMOds	Testes	1	1	1	2	Determining effects of sex chromosome complement in gonadal males
	X X Sox9-overexp.	XXMOds	Testes	2	0	0	2
SF-1 KO (C57BL/6J)
XX SF1-het x XY SF1-het	X Y Sf1-het. mutant	XY SF1-het	Testes	1	1	1	2	Examining the role for sex chromosomes independent of gonadal sex
	X Y Sf1-null mutant	XY SF1-KO	None	1	1	1	2
	X X Sf1-het. mutant	XX SF1-het	Ovaries	2	0	0	2
	X X Sf1-null mutant	XX SF1-KO	None	2	0	0	2
Sex Reversed (C57BL/6J)
XX x XYSxr	X Y-Sxr	XYSxrM	Testes	1	1+ partial	1	2	Determining effects of sex chromosome complement in gonadal males
	X X-Sxr	XXSxrM	Testes	2	partial	1	2

Legend: Model, simplest nomenclature for the offspring produced in these mice; Strain, published strain of models; Dam x Sire, mating pair used to make offspring; Offspring Genotypes, the first X represents the maternally inherited sex chromosome, the second sex chromosome is paternally inherited, and, where applicable, following the paternal sex chromosome are autosomal genetic features that includes transgenic autosomal Sry in the FCG model; Offspring, published names of offspring. NPX, copies of non-PAR X genes; NRY, copies of non-PAR Y genes; Sry, copies of sex-determining region of Y chromosome; PAR, copies of pseudoautosomal region of sex chromosomes. Critical comparisons available within each model are highlighted in gray.

+, Y* and Y*^X chromosomes have a small piece of an NPX consisting of about 8 genes;

−, Y* and X^Y* chromosomes are missing distal PAR which contains the Sts gene;

^acongenic Sry does not cause differentiation into testes in XYPos mice; partial, a small number of Y genes surrounding and including Sry (see text).