Table 1. Clinical characteristics of the kindred.

Individual	Age/sex	TACI (TNFRSF13B) mutation	TCF3 mutation	IgG (g l−1)	IgA (g l−1)	IgM (g l−1)	Memory B cells	Vaccine responses	Autoimmunity	Infectious history	Classificationa	Clinical scoreb
I.1	88/M	C104R	Nil	6	0.9	0.4	ND	ND	ITP	Respiratory	sHGUS	6
I.2	93/F	C104R	Nil	6.3	0.9	2.0	ND	ND	ITP	Respiratory	sHGUS	6
II.2	61/F	C104R	T168fsX191	4.5c	0.2	0.4	Reduced switched memory	Impaired Pneumovax, diphtheria, tetanus toxoids	SLE Hashimoto’s Thyroditis	Respiratory Meningitis Chronic sinusitis Gastrointestinal	CVID-like	34
II.3	55/M	C104R	Nil	9.7	1.5	2.1	Normal	ND	Mild cytopenia	Well	Well	3
II.4	58/M	C104R/C104R	Nil	1.6	0.11	0.67	Reduced switched memory	Transient	Mild cytopenia	Well	Well	3
III.1	35/M	Nil	T168fsX191	5.5	<0.07	0.4	Reduced switched memory	Impaired Pneumovax, diphtheria, tetanus toxoids	T1D Antiparietal Synovitis	Sinusitis Chronic tonsillitis	‘sHGUS’ IgAd	13
III.2	33/F	Nil	Nil	7.1	0.8	0.5	Normal	ND	Nil	Well	Well	0

Abbreviations: sHGUS, symptomatic hypogammaglobulinemia of uncertain significance; SLE, Systemic Lupus Erythematosus; CVID, Common Variable Immunodeficiency Disorders; IVIG, intravenous immunoglobulin; SCIG, subcutaneous immunoglobulin.

^aClassification according the Ameratunga et al.² criteria. sHGUS- symptomatic hypogammaglobulinemia of uncertain significance, IgAd, IgA deficiency; F denotes females, M denotes males. III.1 has been re-designated ‘sHGUS’, as he has an underlying genetic defect. II.2 has been classified as CVID-like, as she now has an underlying genetic cause. Reference ranges IgG 7–14 g l⁻¹, IgA 0.8–4.0 g l⁻¹, IgM 0.4–2.5 g l⁻¹.

^bWe have used the clinical score as an index of severity based on sequelae of the disorder.²¹

^cIgG level of the proband II.2 was obtained in 2002, during a break from IVIG treatment, as result of adverse reactions; her current IgG is unknown because of SCIG treatment. ND, not done; T1D, type 1 diabetes.