
The protein encoded by this gene plays a crucial role in B-cell development. Mutations in this gene cause X-linked agammaglobulinemia type 1, which is an immunodeficiency characterized by the failure to produce mature B lymphocytes, and associated with a failure of Ig heavy chain rearrangement. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Dec 2013].
- Nucleotide binding
- Protein kinase activity
- Enables protein serine/threonine/tyrosine kinase activity
- Enables protein tyrosine kinase activity
- Transmembrane receptor protein tyrosine kinase activity
- Located in nucleus
- Located in cytoplasm
- Located in cytosol
- Located in plasma membrane
- Membrane
- Involved in positive regulation of type III hypersensitivity
- Involved in positive regulation of type I hypersensitivity
- Involved in negative regulation of cytokine production
- Involved in adaptive immune response
- Involved in B cell affinity maturation
Isolated Growth Hormone Deficiency, Type Iii, With Agammaglobulinemia
Isolated Growth Hormone Deficiency Type Iii
Agammaglobulinemia 1, Autosomal Recessive
Polyarticular Juvenile Idiopathic Arthritis
Common Variable Immunodeficiency
Immunodeficiency With Hyper-Igm, Type 1
Splenic Marginal Zone Lymphoma
Plasma Protein Metabolism Disease
- Abnormality of body height
- Recurrent urinary tract infections
- Abnormality of male internal genitalia
- Prostatitis
- Epididymitis
- Abnormality of the genital system
- Abnormality of the urinary system
- Abnormality of the genitourinary system
- Abnormality of head or neck
- Abnormality of the mouth
- Abnormality of the tongue
- Glossoptosis
- Abnormal oral cavity morphology
- Abnormality of the head
- Abnormal paranasal sinus morphology
- Sinusitis
- Abnormality of the face
- Abnormality of the orbital region
- Abnormality of the musculoskeletal system
- Hearing abnormality
- Hearing impairment
- Abnormality of the middle ear
- Otitis media
- Chronic otitis media
- Recurrent otitis media
- Sensorineural hearing impairment
- Abnormal liver morphology
- Abnormality of the eye
- Abnormal conjunctiva morphology
- Conjunctivitis
- Abnormality of the ear
- Abnormality of the nervous system
- Delayed speech and language development
- Abnormal internal genitalia
- Abnormality of the endocrine system
- Delayed puberty
- Decreased response to growth hormone stimulation test
BTK Localizations – Subcellular Localization Database

Pleckstrin homology domain (PH domain) of tyrosine-protein kinase Bruton-Tyrosinkinase (BTK) Protein image from OPM database.
.Gene Location
