Roadmap 2,3,4

client/src/components/GeneticPanelCard.jsx

@@ -0,0 +1,97 @@
+import { useState, useEffect } from 'react'
+import { Dna, Plus } from 'lucide-react'
+import axios from 'axios'
+import GeneticTestForm from './GeneticTestForm'
+
+const RESULT_STYLES = {
+  clear:      { bg: 'rgba(52,199,89,0.15)', color: 'var(--success)' },
+  carrier:    { bg: 'rgba(255,159,10,0.15)', color: 'var(--warning)' },
+  affected:   { bg: 'rgba(255,59,48,0.15)', color: 'var(--danger)' },
+  not_tested: { bg: 'var(--bg-tertiary)', color: 'var(--text-muted)' }
+}
+
+export default function GeneticPanelCard({ dogId }) {
+  const [data, setData] = useState(null)
+  const [error, setError] = useState(false)
+  const [loading, setLoading] = useState(true)
+  const [showForm, setShowForm] = useState(false)
+  const [editingRecord, setEditingRecord] = useState(null)
+
+  const fetchGenetics = () => {
+    setLoading(true)
+    axios.get(`/api/genetics/dog/${dogId}`)
+      .then(res => setData(res.data))
+      .catch(() => setError(true))
+      .finally(() => setLoading(false))
+  }
+
+  useEffect(() => { fetchGenetics() }, [dogId])
+
+  const openAdd = () => { setEditingRecord(null); setShowForm(true) }
+  const openEdit = (rec) => { setEditingRecord(rec); setShowForm(true) }
+  const handleSaved = () => { setShowForm(false); fetchGenetics() }
+
+  if (error || (!loading && !data)) return null
+
+  const panel = data?.panel || []
+  
+  return (
+    <div className="card" style={{ marginBottom: '1.5rem' }}>
+      <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', marginBottom: '1rem' }}>
+        <h2 style={{ fontSize: '1rem', color: 'var(--text-muted)', textTransform: 'uppercase', letterSpacing: '0.05em', margin: 0, display: 'flex', alignItems: 'center', gap: '0.5rem' }}>
+          <Dna size={18} /> DNA Genetics Panel
+        </h2>
+        <button className="btn btn-ghost" style={{ fontSize: '0.8rem', padding: '0.35rem 0.75rem' }} onClick={openAdd}>
+          <Plus size={14} /> Update Marker
+        </button>
+      </div>
+
+      {loading ? (
+        <div style={{ fontSize: '0.875rem', color: 'var(--text-muted)' }}>Loading...</div>
+      ) : (
+        <div style={{ 
+          display: 'grid', gridTemplateColumns: 'repeat(auto-fill, minmax(130px, 1fr))', gap: '0.5rem' 
+        }}>
+          {panel.map(item => {
+            const style = RESULT_STYLES[item.result] || RESULT_STYLES.not_tested
+            // Pass the whole test record if it exists so we can edit it
+            const record = item.id ? item : { marker: item.marker, result: 'not_tested' }
+            
+            return (
+              <div 
+                key={item.marker}
+                onClick={() => openEdit(record)}
+                style={{
+                  padding: '0.5rem 0.75rem',
+                  background: style.bg,
+                  border: `1px solid ${style.color}44`,
+                  borderRadius: 'var(--radius-sm)',
+                  cursor: 'pointer',
+                  transition: 'transform 0.1s ease',
+                }}
+                onMouseEnter={e => e.currentTarget.style.transform = 'translateY(-2px)'}
+                onMouseLeave={e => e.currentTarget.style.transform = 'translateY(0)'}
+              >
+                <div style={{ fontSize: '0.75rem', color: 'var(--text-muted)', marginBottom: '0.2rem', fontWeight: 500 }}>
+                  {item.marker}
+                </div>
+                <div style={{ fontSize: '0.875rem', color: style.color, fontWeight: 600, textTransform: 'capitalize' }}>
+                  {item.result.replace('_', ' ')}
+                </div>
+              </div>
+            )
+          })}
+        </div>
+      )}
+
+      {showForm && (
+        <GeneticTestForm
+          dogId={dogId}
+          record={editingRecord}
+          onClose={() => setShowForm(false)}
+          onSave={handleSaved}
+        />
+      )}
+    </div>
+  )
+}

client/src/components/GeneticTestForm.jsx

@@ -0,0 +1,157 @@
+import { useState } from 'react'
+import { X } from 'lucide-react'
+import axios from 'axios'
+
+const GR_MARKERS = [
+  { value: 'PRA1', label: 'PRA1' },
+  { value: 'PRA2', label: 'PRA2' },
+  { value: 'prcd-PRA', label: 'prcd-PRA' },
+  { value: 'GR-PRA1', label: 'GR-PRA1' },
+  { value: 'GR-PRA2', label: 'GR-PRA2' },
+  { value: 'ICH1', label: 'ICH1 (Ichthyosis 1)' },
+  { value: 'ICH2', label: 'ICH2 (Ichthyosis 2)' },
+  { value: 'NCL', label: 'Neuronal Ceroid Lipofuscinosis' },
+  { value: 'DM', label: 'Degenerative Myelopathy' },
+  { value: 'MD', label: 'Muscular Dystrophy' }
+]
+
+const RESULTS = [
+  { value: 'clear', label: 'Clear / Normal' },
+  { value: 'carrier', label: 'Carrier (1 copy)' },
+  { value: 'affected', label: 'Affected / At Risk (2 copies)' },
+  { value: 'not_tested', label: 'Not Tested' }
+]
+
+const EMPTY = {
+  test_provider: 'Embark',
+  marker: 'PRA1',
+  result: 'clear',
+  test_date: '',
+  document_url: '',
+  notes: ''
+}
+
+export default function GeneticTestForm({ dogId, record, onClose, onSave }) {
+  const [form, setForm] = useState(record || { ...EMPTY, dog_id: dogId })
+  const [saving, setSaving] = useState(false)
+  const [error, setError] = useState(null)
+
+  const set = (k, v) => setForm(f => ({ ...f, [k]: v }))
+
+  const handleSubmit = async (e) => {
+    e.preventDefault()
+    setSaving(true)
+    setError(null)
+    
+    // If not tested, don't save
+    if (form.result === 'not_tested' && !record) {
+      setError('Cannot save a "Not Tested" result. Please just delete the record if it exists.')
+      setSaving(false)
+      return
+    }
+
+    try {
+      if (record && record.id) {
+        if (form.result === 'not_tested') {
+          // If changed to not_tested, just delete it
+          await axios.delete(`/api/genetics/${record.id}`)
+        } else {
+          await axios.put(`/api/genetics/${record.id}`, form)
+        }
+      } else {
+        await axios.post('/api/genetics', { ...form, dog_id: dogId })
+      }
+      onSave()
+    } catch (err) {
+      setError(err.response?.data?.error || 'Failed to save genetic record')
+    } finally {
+      setSaving(false)
+    }
+  }
+
+  const labelStyle = {
+    fontSize: '0.8rem', color: 'var(--text-muted)',
+    marginBottom: '0.25rem', display: 'block',
+  }
+  const inputStyle = {
+    width: '100%', background: 'var(--bg-primary)',
+    border: '1px solid var(--border)', borderRadius: 'var(--radius-sm)',
+    padding: '0.5rem 0.75rem', color: 'var(--text-primary)', fontSize: '0.9rem',
+    boxSizing: 'border-box',
+  }
+  const fw = { display: 'flex', flexDirection: 'column', gap: '0.25rem' }
+
+  return (
+    <div style={{
+      position: 'fixed', inset: 0, background: 'rgba(0,0,0,0.7)',
+      backdropFilter: 'blur(4px)', display: 'flex', alignItems: 'center',
+      justifyContent: 'center', zIndex: 1000, padding: '1rem',
+    }}>
+      <div className="card" style={{
+        width: '100%', maxWidth: '500px', maxHeight: '90vh',
+        overflowY: 'auto', position: 'relative',
+      }}>
+        <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', marginBottom: '1.5rem' }}>
+          <h2 style={{ margin: 0 }}>{record && record.id ? 'Edit' : 'Add'} Genetic Result</h2>
+          <button className="btn-icon" onClick={onClose}><X size={20} /></button>
+        </div>
+
+        <form onSubmit={handleSubmit} style={{ display: 'flex', flexDirection: 'column', gap: '1rem' }}>
+          <div style={{ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: '1rem' }}>
+            <div style={fw}>
+              <label style={labelStyle}>Marker *</label>
+              <select style={inputStyle} value={form.marker} onChange={e => set('marker', e.target.value)} disabled={!!record}>
+                {GR_MARKERS.map(m => <option key={m.value} value={m.value}>{m.label}</option>)}
+              </select>
+            </div>
+            <div style={fw}>
+              <label style={labelStyle}>Result *</label>
+              <select style={inputStyle} value={form.result} onChange={e => set('result', e.target.value)}>
+                {RESULTS.map(r => <option key={r.value} value={r.value}>{r.label}</option>)}
+              </select>
+            </div>
+          </div>
+
+          <div style={{ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: '1rem' }}>
+            <div style={fw}>
+              <label style={labelStyle}>Provider</label>
+              <input style={inputStyle} placeholder="Embark, PawPrint, etc." value={form.test_provider}
+                onChange={e => set('test_provider', e.target.value)} />
+            </div>
+            <div style={fw}>
+              <label style={labelStyle}>Test Date</label>
+              <input style={inputStyle} type="date" value={form.test_date}
+                onChange={e => set('test_date', e.target.value)} />
+            </div>
+          </div>
+
+          <div style={fw}>
+            <label style={labelStyle}>Document URL</label>
+            <input style={inputStyle} type="url" placeholder="Link to PDF or result page" value={form.document_url}
+              onChange={e => set('document_url', e.target.value)} />
+          </div>
+
+          <div style={fw}>
+            <label style={labelStyle}>Notes</label>
+            <textarea style={{ ...inputStyle, minHeight: '60px', resize: 'vertical' }}
+              value={form.notes} onChange={e => set('notes', e.target.value)} />
+          </div>
+
+          {error && (
+            <div style={{
+              color: 'var(--danger)', fontSize: '0.85rem', padding: '0.5rem 0.75rem',
+              background: 'rgba(255,59,48,0.1)', borderRadius: 'var(--radius-sm)',
+            }}>{error}</div>
+          )}
+
+          <div style={{ display: 'flex', gap: '0.75rem', justifyContent: 'flex-end', marginTop: '0.5rem' }}>
+            <button type="button" className="btn btn-ghost" onClick={onClose}>Cancel</button>
+            <button type="submit" className="btn btn-primary" disabled={saving}>
+              {saving ? 'Saving...' : 'Save Result'}
+            </button>
+          </div>
+        </form>
+      </div>
+    </div>
+  )
+}

client/src/components/PedigreeView.jsx

@@ -17,19 +17,24 @@ function PedigreeView({ dogId, onClose }) {
   }, [dogId])
 
   useEffect(() => {
-    const updateDimensions = () => {
     const container = document.querySelector('.pedigree-container')
-      if (container) {
+    if (!container) return
+
+    const updateDimensions = () => {
       const width = container.offsetWidth
       const height = container.offsetHeight
       setDimensions({ width, height })
       setTranslate({ x: width / 4, y: height / 2 })
     }
-    }
     
     updateDimensions()
-    window.addEventListener('resize', updateDimensions)
-    return () => window.removeEventListener('resize', updateDimensions)
+    
+    const resizeObserver = new ResizeObserver(() => {
+      updateDimensions()
+    })
+    resizeObserver.observe(container)
+    
+    return () => resizeObserver.disconnect()
   }, [])
 
   const fetchPedigree = async () => {

client/src/pages/DogDetail.jsx

@@ -6,6 +6,8 @@ import DogForm from '../components/DogForm'
 import { ChampionBadge, ChampionBloodlineBadge } from '../components/ChampionBadge'
 import ClearanceSummaryCard from '../components/ClearanceSummaryCard'
 import HealthRecordForm from '../components/HealthRecordForm'
+import GeneticPanelCard from '../components/GeneticPanelCard'
+import { ShieldCheck } from 'lucide-react'
 
 function DogDetail() {
   const { id } = useParams()
@@ -262,6 +264,18 @@ function DogDetail() {
                   <span className="info-value" style={{ fontFamily: 'monospace' }}>{dog.registration_number}</span>
                 </div>
               )}
+              {dog.chic_number && (
+                <div className="info-row">
+                  <span className="info-label"><ShieldCheck size={14} style={{ display: 'inline', marginRight: '0.25rem' }} />CHIC Status</span>
+                  <span className="info-value">
+                    <span style={{
+                      fontSize: '0.75rem', fontWeight: 600, padding: '0.2rem 0.6rem',
+                      background: 'rgba(99,102,241,0.15)', color: '#818cf8',
+                      borderRadius: '999px', border: '1px solid rgba(99,102,241,0.3)'
+                    }}>CHIC #{dog.chic_number}</span>
+                  </span>
+                </div>
+              )}
               {dog.microchip && (
                 <div className="info-row">
                   <span className="info-label"><Hash size={14} style={{ display: 'inline', marginRight: '0.25rem' }} />Microchip</span>
@@ -317,6 +331,9 @@ function DogDetail() {
       {/* OFA Clearance Summary */}
       <ClearanceSummaryCard dogId={id} onAddRecord={openAddHealth} />
 
+      {/* DNA Genetics Panel */}
+      <GeneticPanelCard dogId={id} />
+
       {/* Health Records List */}
       {healthRecords.length > 0 && (
         <div className="card" style={{ marginBottom: '1.5rem' }}>

client/src/pages/DogList.jsx

@@ -259,6 +259,19 @@ function DogList() {
                     {dog.registration_number}
                   </div>
                 )}
+                {dog.chic_number && (
+                  <div style={{
+                    display: 'inline-flex', alignItems: 'center', gap: '0.25rem',
+                    padding: '0.25rem 0.5rem',
+                    background: 'rgba(99,102,241,0.1)',
+                    border: '1px solid rgba(99,102,241,0.3)',
+                    borderRadius: 'var(--radius-sm)',
+                    fontSize: '0.75rem', fontWeight: 600,
+                    color: '#818cf8', marginLeft: '0.5rem'
+                  }}>
+                    CHIC #{dog.chic_number}
+                  </div>
+                )}
               </Link>
 
               {/* Actions */}

client/src/pages/PairingSimulator.jsx

@@ -11,6 +11,8 @@ export default function PairingSimulator() {
   const [dogsLoading, setDogsLoading] = useState(true)
   const [relationWarning, setRelationWarning] = useState(null)
   const [relationChecking, setRelationChecking] = useState(false)
+  const [geneticRisk, setGeneticRisk] = useState(null)
+  const [geneticChecking, setGeneticChecking] = useState(false)
 
   useEffect(() => {
     // include_external=1 ensures external sires/dams appear for pairing
@@ -27,17 +29,28 @@ export default function PairingSimulator() {
   const checkRelation = useCallback(async (sid, did) => {
     if (!sid || !did) {
       setRelationWarning(null)
+      setGeneticRisk(null)
       return
     }
     setRelationChecking(true)
+    setGeneticChecking(true)
     try {
-      const res = await fetch(`/api/pedigree/relations/${sid}/${did}`)
-      const data = await res.json()
-      setRelationWarning(data.related ? data.relationship : null)
+      const [relRes, genRes] = await Promise.all([
+        fetch(`/api/pedigree/relations/${sid}/${did}`),
+        fetch(`/api/genetics/pairing-risk?sireId=${sid}&damId=${did}`)
+      ])
+      
+      const relData = await relRes.json()
+      setRelationWarning(relData.related ? relData.relationship : null)
+      
+      const genData = await genRes.json()
+      setGeneticRisk(genData)
     } catch {
       setRelationWarning(null)
+      setGeneticRisk(null)
     } finally {
       setRelationChecking(false)
+      setGeneticChecking(false)
     }
   }, [])
 
@@ -142,7 +155,7 @@ export default function PairingSimulator() {
 
           {relationChecking && (
             <div style={{ fontSize: '0.85rem', color: 'var(--text-muted)', marginBottom: '0.75rem' }}>
-              Checking relationship...
+              Checking relationship and genetics...
             </div>
           )}
 
@@ -158,6 +171,31 @@ export default function PairingSimulator() {
             </div>
           )}
 
+          {geneticRisk && geneticRisk.risks && geneticRisk.risks.length > 0 && !geneticChecking && (
+            <div style={{
+              padding: '0.6rem 1rem', marginBottom: '0.75rem',
+              background: 'rgba(255,159,10,0.08)', border: '1px solid rgba(255,159,10,0.3)',
+              borderRadius: 'var(--radius)', fontSize: '0.875rem', color: 'var(--warning)',
+            }}>
+              <div style={{ display: 'flex', alignItems: 'center', gap: '0.5rem', marginBottom: '0.25rem', fontWeight: 600 }}>
+                <ShieldAlert size={16} /> Genetic Risks Detected
+              </div>
+              <ul style={{ margin: 0, paddingLeft: '1.5rem' }}>
+                {geneticRisk.risks.map(r => (
+                  <li key={r.marker}>
+                    <strong>{r.marker}</strong>: {r.message}
+                  </li>
+                ))}
+              </ul>
+            </div>
+          )}
+
+          {geneticRisk && geneticRisk.missing_data && !geneticChecking && (
+            <div style={{ fontSize: '0.8rem', color: 'var(--text-muted)', marginBottom: '0.75rem', fontStyle: 'italic' }}>
+              * Sire or dam has missing genetic tests. Clearances cannot be fully verified.
+            </div>
+          )}
+
           <button
             type="submit"
             className="btn btn-primary"

server/db/init.js

@@ -157,6 +157,18 @@ function initDatabase() {
     )
   `);
 
+  const geneticMigrations = [
+    ['test_provider', 'TEXT'],
+    ['marker', "TEXT NOT NULL DEFAULT 'unknown'"],
+    ['result', "TEXT NOT NULL DEFAULT 'not_tested'"],
+    ['test_date', 'TEXT'],
+    ['document_url', 'TEXT'],
+    ['notes', 'TEXT']
+  ];
+  for (const [col, def] of geneticMigrations) {
+    try { db.exec(`ALTER TABLE genetic_tests ADD COLUMN ${col} ${def}`); } catch (_) {}
+  }
+
   // ── Cancer History ────────────────────────────────────────────────────────
   db.exec(`
     CREATE TABLE IF NOT EXISTS cancer_history (
@@ -173,6 +185,17 @@ function initDatabase() {
     )
   `);
 
+  const cancerMigrations = [
+    ['cancer_type', 'TEXT'],
+    ['age_at_diagnosis', 'TEXT'],
+    ['age_at_death', 'TEXT'],
+    ['cause_of_death', 'TEXT'],
+    ['notes', 'TEXT']
+  ];
+  for (const [col, def] of cancerMigrations) {
+    try { db.exec(`ALTER TABLE cancer_history ADD COLUMN ${col} ${def}`); } catch (_) {}
+  }
+
   // ── Settings ──────────────────────────────────────────────────────────────
   db.exec(`
     CREATE TABLE IF NOT EXISTS settings (

server/routes/health.js

@@ -10,6 +10,7 @@ const GRCA_CORE = {
   heart:  ['heart_ofa', 'heart_echo'],
   eye:    ['eye_caer'],
 };
+const VALID_TEST_TYPES = ['hip_ofa', 'hip_pennhip', 'elbow_ofa', 'heart_ofa', 'heart_echo', 'eye_caer', 'thyroid_ofa', 'dna_panel'];
 
 // Helper: compute clearance summary for a dog
 function getClearanceSummary(db, dogId) {
@@ -103,17 +104,6 @@ router.get('/dog/:dogId/chic-eligible', (req, res) => {
   }
 });
 
-// GET single health record
-router.get('/:id', (req, res) => {
-  try {
-    const db = getDatabase();
-    const record = db.prepare('SELECT * FROM health_records WHERE id = ?').get(req.params.id);
-    if (!record) return res.status(404).json({ error: 'Health record not found' });
-    res.json(record);
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
 
 // POST create health record
 router.post('/', (req, res) => {
@@ -128,6 +118,10 @@ router.post('/', (req, res) => {
       return res.status(400).json({ error: 'dog_id, record_type, and test_date are required' });
     }
 
+    if (test_type && !VALID_TEST_TYPES.includes(test_type)) {
+      return res.status(400).json({ error: 'Invalid test_type' });
+    }
+
     const db = getDatabase();
     const dbResult = db.prepare(`
       INSERT INTO health_records
@@ -157,6 +151,10 @@ router.put('/:id', (req, res) => {
       document_url, result, vet_name, next_due, notes
     } = req.body;
 
+    if (test_type && !VALID_TEST_TYPES.includes(test_type)) {
+      return res.status(400).json({ error: 'Invalid test_type' });
+    }
+
     const db = getDatabase();
     db.prepare(`
       UPDATE health_records
@@ -190,4 +188,70 @@ router.delete('/:id', (req, res) => {
   }
 });
 
+// GET cancer history for a dog
+router.get('/dog/:dogId/cancer-history', (req, res) => {
+  try {
+    const db = getDatabase();
+    const records = db.prepare(`
+      SELECT * FROM cancer_history
+      WHERE dog_id = ?
+      ORDER BY age_at_diagnosis ASC, created_at DESC
+    `).all(req.params.dogId);
+    res.json(records);
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+// POST create cancer history record
+router.post('/cancer-history', (req, res) => {
+  try {
+    const {
+      dog_id, cancer_type, age_at_diagnosis, age_at_death, cause_of_death, notes
+    } = req.body;
+
+    if (!dog_id || !cancer_type) {
+      return res.status(400).json({ error: 'dog_id and cancer_type are required' });
+    }
+
+    const db = getDatabase();
+    
+    // Update dog's age_at_death and cause_of_death if provided
+    if (age_at_death || cause_of_death) {
+      db.prepare(`
+        UPDATE dogs SET 
+          age_at_death = COALESCE(?, age_at_death),
+          cause_of_death = COALESCE(?, cause_of_death)
+        WHERE id = ?
+      `).run(age_at_death || null, cause_of_death || null, dog_id);
+    }
+
+    const dbResult = db.prepare(`
+      INSERT INTO cancer_history
+        (dog_id, cancer_type, age_at_diagnosis, age_at_death, cause_of_death, notes)
+      VALUES (?, ?, ?, ?, ?, ?)
+    `).run(
+      dog_id, cancer_type, age_at_diagnosis || null, 
+      age_at_death || null, cause_of_death || null, notes || null
+    );
+
+    const record = db.prepare('SELECT * FROM cancer_history WHERE id = ?').get(dbResult.lastInsertRowid);
+    res.status(201).json(record);
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+// GET single health record (wildcard should go last to prevent overlap)
+router.get('/:id', (req, res) => {
+  try {
+    const db = getDatabase();
+    const record = db.prepare('SELECT * FROM health_records WHERE id = ?').get(req.params.id);
+    if (!record) return res.status(404).json({ error: 'Health record not found' });
+    res.json(record);
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
 module.exports = router;

server/routes/pedigree.js

@@ -2,6 +2,25 @@ const express = require('express');
 const router = express.Router();
 const { getDatabase } = require('../db/init');
 
+const MAX_CACHE_SIZE = 1000;
+const ancestorCache = new Map();
+const coiCache = new Map();
+
+function getFromCache(cache, key, computeFn) {
+  if (cache.has(key)) {
+    const val = cache.get(key);
+    cache.delete(key);
+    cache.set(key, val);
+    return val;
+  }
+  const val = computeFn();
+  if (cache.size >= MAX_CACHE_SIZE) {
+    cache.delete(cache.keys().next().value);
+  }
+  cache.set(key, val);
+  return val;
+}
+
 /**
  * getAncestorMap(db, dogId, maxGen)
  * Returns Map<id, [{ id, name, generation }, ...]>
@@ -9,6 +28,8 @@ const { getDatabase } = require('../db/init');
  * pairings are correctly detected by calculateCOI.
  */
 function getAncestorMap(db, dogId, maxGen = 6) {
+  const cacheKey = `${dogId}-${maxGen}`;
+  return getFromCache(ancestorCache, cacheKey, () => {
     const map = new Map();
 
     function recurse(id, gen) {
@@ -27,6 +48,7 @@ function getAncestorMap(db, dogId, maxGen = 6) {
 
     recurse(parseInt(dogId), 0);
     return map;
+  });
 }
 
 /**
@@ -68,6 +90,8 @@ function isDirectRelation(db, sireId, damId) {
  * self-loops.
  */
 function calculateCOI(db, sireId, damId) {
+  const cacheKey = `${sireId}-${damId}`;
+  return getFromCache(coiCache, cacheKey, () => {
     const sid = parseInt(sireId);
     const did = parseInt(damId);
     const sireMap = getAncestorMap(db, sid);
@@ -116,6 +140,7 @@ function calculateCOI(db, sireId, damId) {
       coefficient:     coi,
       commonAncestors: commonAncestorList
     };
+  });
 }
 
 // =====================================================================
@@ -195,6 +220,63 @@ router.get('/relations/:sireId/:damId', (req, res) => {
   }
 });
 
+// GET /api/pedigree/:id/cancer-lineage
+router.get('/:id/cancer-lineage', (req, res) => {
+  try {
+    const db = getDatabase();
+    // Get ancestor map up to 5 generations
+    const ancestorMap = getAncestorMap(db, req.params.id, 5);
+    
+    // Collect all unique ancestor IDs
+    const ancestorIds = Array.from(ancestorMap.keys());
+    
+    if (ancestorIds.length === 0) {
+      return res.json({ lineage_cases: [], stats: { total_ancestors: 0, ancestors_with_cancer: 0 } });
+    }
+    
+    // Query cancer history for all ancestors
+    const placeholders = ancestorIds.map(() => '?').join(',');
+    const cancerRecords = db.prepare(`
+      SELECT c.*, d.name, d.sex 
+      FROM cancer_history c
+      JOIN dogs d ON c.dog_id = d.id
+      WHERE c.dog_id IN (${placeholders})
+    `).all(...ancestorIds);
+    
+    // Structure the response
+    const cases = cancerRecords.map(record => {
+      // Find the closest generation this ancestor appears in
+      const occurrences = ancestorMap.get(record.dog_id);
+      const closestGen = occurrences.reduce((min, occ) => occ.generation < min ? occ.generation : min, 999);
+      
+      return {
+        ...record,
+        generation_distance: closestGen
+      };
+    });
+    
+    // Sort by generation distance (closer relatives first)
+    cases.sort((a, b) => a.generation_distance - b.generation_distance);
+    
+    // Count unique dogs with cancer (excluding generation 0 if we only want stats on ancestors)
+    const ancestorCases = cases.filter(c => c.generation_distance > 0);
+    const uniqueAncestorsWithCancer = new Set(ancestorCases.map(c => c.dog_id)).size;
+    
+    // Number of ancestors is total unique IDs minus 1 for the dog itself
+    const numAncestors = ancestorIds.length > 0 && ancestorMap.get(parseInt(req.params.id)) ? ancestorIds.length - 1 : ancestorIds.length;
+    
+    res.json({
+      lineage_cases: cases,
+      stats: {
+        total_ancestors: numAncestors,
+        ancestors_with_cancer: uniqueAncestorsWithCancer
+      }
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
 // =====================================================================
 // Wildcard routes last
 // =====================================================================