Table 1 Candidate genes investigated in restless legs syndrome and linkage analysis identified so far.

Candidate gene	Linkage
1. DA receptor genes
D1–D5 receptors	Nil
DAT	Nil
TH	Nil
Dopamine β hydroxylase	Nil
2. GTP cyclohydrolase	Nil
3. GABA A receptor subunits (α1–6, β1–3, χ1–3, p1–2)	Nil
4. α‐1 subunit of the glycine receptor (chromosome 5q31)	Nil
5. MAO‐A	Nil
6. MAO	Nil
7. Neurotensin	Nil

DA, dopamine; DAT, dopamine transporter; GABA, γ‐amonibutyric acid; GTP, guanosine triphosphate; MAO, monoamine oxidase; TH, tryosine hydroxylase.