{
  "url": "https://dantelabs.com/traits/knuckle-pad",
  "trait": {
    "bundleId": "2026.10.17-8666dff2",
    "release": "2026-09-01",
    "slug": "knuckle-pad",
    "id": "HP:0032541",
    "name": "Knuckle pad",
    "definition": "Knuckle pads are benign fibrofatty subcutaneous pads located over the proximal interphalangeal (PIP) joints that can be mistaken for arthritis. Rarely they affect the dorsal aspect of the metacarpophalangeal (MCP) joints. Clinically they are painless and often affect both hands in an asymmetrical pattern.",
    "synonyms": [
      "DDN",
      "Dorsal dupuytren nodules",
      "Knuckle pads on dorsal aspect of finger joints"
    ],
    "systems": [
      {
        "slug": "abnormality-of-the-integument",
        "name": "Abnormality of the integument",
        "url": "https://dantelabs.com/traits/abnormality-of-the-integument"
      }
    ],
    "broader": [
      {
        "slug": "regional-abnormality-of-skin",
        "name": "Regional abnormality of skin",
        "url": "https://dantelabs.com/traits/regional-abnormality-of-skin"
      }
    ],
    "narrower": [],
    "genes": [
      {
        "slug": "krt1",
        "symbol": "KRT1",
        "hgnc": "HGNC:6412",
        "name": "keratin 1",
        "frequency": "obligate",
        "diseases": 3,
        "url": "https://dantelabs.com/genes/krt1"
      },
      {
        "slug": "gjb2",
        "symbol": "GJB2",
        "hgnc": "HGNC:4284",
        "name": "gap junction protein beta 2",
        "frequency": "very-frequent",
        "diseases": 3,
        "url": "https://dantelabs.com/genes/gjb2"
      },
      {
        "slug": "smarcad1",
        "symbol": "SMARCAD1",
        "hgnc": "HGNC:18398",
        "name": "SNF2 related chromatin remodeling ATPase with DExD box 1",
        "frequency": "very-frequent",
        "diseases": 1,
        "url": "https://dantelabs.com/genes/smarcad1"
      },
      {
        "slug": "aqp5",
        "symbol": "AQP5",
        "hgnc": "HGNC:638",
        "name": "aquaporin 5",
        "frequency": "frequent",
        "diseases": 1,
        "url": "https://dantelabs.com/genes/aqp5"
      },
      {
        "slug": "kdf1",
        "symbol": "KDF1",
        "hgnc": "HGNC:26624",
        "name": "keratinocyte differentiation factor 1",
        "frequency": "frequent",
        "diseases": 1,
        "url": "https://dantelabs.com/genes/kdf1"
      },
      {
        "slug": "krt16",
        "symbol": "KRT16",
        "hgnc": "HGNC:6423",
        "name": "keratin 16",
        "frequency": "frequent",
        "diseases": 1,
        "url": "https://dantelabs.com/genes/krt16"
      },
      {
        "slug": "krt9",
        "symbol": "KRT9",
        "hgnc": "HGNC:6447",
        "name": "keratin 9",
        "frequency": "frequent",
        "diseases": 1,
        "url": "https://dantelabs.com/genes/krt9"
      },
      {
        "slug": "loricrin",
        "symbol": "LORICRIN",
        "hgnc": "HGNC:6663",
        "name": "loricrin cornified envelope precursor protein",
        "frequency": "frequent",
        "diseases": 1,
        "url": "https://dantelabs.com/genes/loricrin"
      },
      {
        "slug": "cast",
        "symbol": "CAST",
        "hgnc": "HGNC:1515",
        "name": "calpastatin",
        "frequency": "occasional",
        "diseases": 1,
        "url": "https://dantelabs.com/genes/cast"
      }
    ]
  }
}