| Syndrome |
Gene |
Chromosome |
Location |
Category |
| Bainbridge-Ropers syndrome | ASXL3 | 18 | q12.1 | Autism spectrum | |
| Bainbridge-Ropers syndrome | BRPS | 18 | q12.1 | Autism spectrum | |
| Baraitser-Winter syndrome | ACTB | 7 | p22.1 | Autism spectrum | |
| Baraitser-Winter syndrome | ACTG1 | 17 | q25.3 | Autism spectrum | |
| BECKWITH-WIEDEMANN SYNDROME | CDKN1C | 11 | p15.4 | Autism spectrum | |
| BECKWITH-WIEDEMANN SYNDROME | H19 | 11 | p15.5 | Autism spectrum | |
| BECKWITH-WIEDEMANN SYNDROME | ICR1 | 11 | p15.5 | Autism spectrum | |
| BECKWITH-WIEDEMANN SYNDROME | KCNQ1OT1 | 11 | p15.5 | Autism spectrum | |
| Behr syndrome | OPA1-both | 3 | q29 | Ataxia spectrum | |
| Benign familial neonatal seizures | KCNQ2 | 20 | q13.33 | Epilepsy and seizures | |
| Benign familial neonatal seizures | KCNQ3 | 8 | q24.22 | Epilepsy and seizures | |
| Beta-propeller protein-associated neurodegeneration | WDR45 | 23 | p11.23 | Ataxia spectrum | |
| beta-propeller protein-associated neurodegeneration | WDR45 | 23 | p11.23 | Epilepsy and seizures | |
| Beta-ureidopropionase deficiency | UPB1 | 22 | q11.2 | Microcephaly | |
| Biotinidase deficiency | BTD | 3 | p25.1 | Alopecia | |
| Biotin-thiamine-responsive basal ganglia disease | SLC19A3 | 2 | q36.3 | Ataxia spectrum | |
| Blau syndrome | NOD2 | 16 | q12.1 | Photophobia - sensitivity to light | |
| Boerjeson-Forssman-Lehmann syndrome | PHF6 | 23 | q26.2 | Epilepsy and seizures | |
| BOSCH-BOONSTRA-SCHAAF OPTIC ATROPHY SYNDROME | BBSOAS | 5 | q15 | Autism spectrum | |
| Bowen-Conradi syndrome | EMG1 | 12 | p13.3 | Cleft lip / cleft palate | |
| BRACHYCEPHALY TRICHOMEGALY AND DEVELOPMENTAL DELAY | BTDD | 5 | q14.2 | Autism spectrum | |
| Brachydactyly-mental retardation syndrome | HDAC4 | 2 | q37.3 | Autism spectrum | |
| Brain-lung-thyroid syndrome | NKX2-1 | 14 | q13.3 | Hypothyroidism | |
| BRANCHED-CHAIN KETO ACID DEHYDROGENASE KINASE DEFICIENCY | BCKDKD | 16 | p11.2 | Autism spectrum | |
| Branched-chain ketoacid dehydrogenase kinase deficiency | BCKDK | 16 | p11.2 | Autism spectrum | |
| Branchio-oculo-facial syndrome | TFAP2A | 6 | p24 | Cleft lip / cleft palate | |
| Brown-Vialetto-Van Laere syndrome (BVVLS) | SLC52A3 | 20 | p13 | Cerebral palsy | |
| BRUNNER SYNDROME | BRNRS | 23 | p11.3 | Autism spectrum | |
| Burn-McKeown syndrome | TXNL4A | 18 | q23 | Cleft lip / cleft palate | |