What it can look like: the whole range
Kidneys and urinary tract, pancreas/diabetes, liver enzymes, reproductive anatomy, development, speech, behaviour, and occasionally seizures or heart differences. Any subset is possible - including none at all.
Not everyone gets everything. Think of it as a menu of possible features rather than a fixed list:
Kidneys and urinary tract (the most consistent group)
- Differences in kidney size/shape, cysts, a single kidney, reflux, or reduced kidney function.
- Some people have no kidney symptoms at all and only a difference visible on an ultrasound.
Diabetes and pancreas
- Diabetes can start in childhood, teenage years or adulthood (the type historically called MODY5).
- The pancreas can be smaller than usual or not make enough digestive enzymes; some people get
unexplained belly pain or abnormal liver/pancreas blood tests.
Learning, speech and behaviour
- Delayed walking and, very commonly, delayed or disordered speech (childhood apraxia of speech is
often described).
- Learning support needs range from none to intellectual disability; specific difficulties with maths
and non-verbal learning are frequently reported.
- Higher rates of autism spectrum traits, ADHD, anxiety; in adolescence/adulthood, a raised risk of
psychosis/schizophrenia compared with the general population.
Other possible features
- In females: differences in the shape of the uterus/vagina (e.g. uterus didelphys, MRKH sequence).
- Feeding difficulties and failure to thrive in infancy; growth is usually normal.
- Eye (refractive errors, strabismus), hearing differences, raised liver enzymes, occasionally a
congenital heart difference or seizures.
- Some individuals have no symptoms and are only identified after their child is diagnosed.
Freshest finding: A source describes a new or expanded observation: “In conclusion, here we report a novel model of non-small cell lung cancer driven by a mutation in Kras and deletion of Mst1/2 kinases.”
Feature frequency (as reported in published cohorts)
Published series differ because they are biased by who got tested (renal clinics vs. developmental clinics vs. prenatal ascertainment). Approximate ranges from the literature:
| Feature | Reported range |
|---|---|
| Renal anomalies (any) | ~50-80% |
| Renal cysts / hypodysplasia / single kidney | ~30-50% |
| Reduced kidney function / chronic kidney disease | ~10-25% |
| Diabetes (HNF1B-related) | ~20-50% (age-dependent, often adolescence/adulthood) |
| Pancreatic anomalies / abnormal pancreatic enzymes | ~10-40% |
| Abnormal liver enzymes | ~10-30% |
| Developmental delay | ~50-70% |
| Speech/language disorder (incl. apraxia of speech) | ~50-70% |
| Learning disability / intellectual disability | ~20-50% (mild most common) |
| Autism spectrum | ~10-25% |
| ADHD / behavioural differences | ~20-40% |
| Psychosis / schizophrenia-spectrum | raised risk vs. population (small absolute numbers) |
| Seizures / epilepsy | ~5-15% |
| Müllerian anomalies (assigned female) | ~10-30% (higher in targeted imaging studies) |
| Congenital heart differences | ~5-10% |
Read these numbers with care. They come from different ascertainment schemes and different breakpoint definitions; the "Latest evidence" section below shows what the corpus currently supports and links to the exact sentences.
Why so variable?
Three overlapping explanations appear in the literature:
- Second-hit variation - modifier variants elsewhere in the genome (and on the other HNF1B copy).
- Which genes are actually in the interval - atypical (smaller/larger) deletions and duplications
shift the picture.
- Chance and ascertainment - mild carriers are never tested, so clinic-based numbers overstate
severity.
Latest evidence in the collected corpus
New observation reported: In conclusion, here we report a novel model of non-small cell lung cancer driven by a mutation in Kras and del…
A source describes a new or expanded observation: “In conclusion, here we report a novel model of non-small cell lung cancer driven by a mutation in Kras and deletion of Mst1/2 kinases.”
“In conclusion, here we report a novel model of non-small cell lung cancer driven by a mutation in Kras and deletion of Mst1/2 kinases.”corroboration 1 · confidence 97% · updated 2026-11-14 · source
New observation reported: Here, we report a novel case of a syndromic HNF1B -deficient paediatric patient that developed HCC with unique…
A source describes a new or expanded observation: “Here, we report a novel case of a syndromic HNF1B -deficient paediatric patient that developed HCC with unique histopathological features characterised by neoplastic syncytial giant cells, which was observed only in one additional case of paediatric cholestatic liver disease of unknown origin.”
“Here, we report a novel case of a syndromic HNF1B -deficient paediatric patient that developed HCC with unique histopathological features characterised by neoplastic syncytial giant cells, which was observed only in one additional case of paediatric…”corroboration 1 · confidence 97% · updated 2026-11-14 · source
New observation reported: We reported for the first time three patients with cardiac and great artery malformations…
A source describes a new or expanded observation: “We reported for the first time three patients with cardiac and great artery malformations.”
“We reported for the first time three patients with cardiac and great artery malformations.”corroboration 1 · confidence 97% · updated 2026-11-14 · source
New observation reported: However, there were many highly significant genes showing novel isoforms in our data that were not previously …
A source describes a new or expanded observation: “However, there were many highly significant genes showing novel isoforms in our data that were not previously associated with cancer.”
“However, there were many highly significant genes showing novel isoforms in our data that were not previously associated with cancer.”corroboration 1 · confidence 97% · updated 2026-11-14 · source
New observation reported: For the first time we report about a patient with a 17q12 microdeletion who is affected by MRKH in combination…
A source describes a new or expanded observation: “For the first time we report about a patient with a 17q12 microdeletion who is affected by MRKH in combination with a vascular and soft tissue disorder.”
“For the first time we report about a patient with a 17q12 microdeletion who is affected by MRKH in combination with a vascular and soft tissue disorder.”corroboration 1 · confidence 97% · updated 2026-11-14 · source
New observation reported: (C) According to the results of enrichment analysis of Gene Ontology, we found, for the first time, that LHX1 …
A source describes a new or expanded observation: “(C) According to the results of enrichment analysis of Gene Ontology, we found, for the first time, that LHX1 gene affects the urinary system and GGNBP2 and LHX1 genes affect the development of the female reproductive system.”
“(C) According to the results of enrichment analysis of Gene Ontology, we found, for the first time, that LHX1 gene affects the urinary system and GGNBP2 and LHX1 genes affect the development of the female reproductive system.”corroboration 1 · confidence 97% · updated 2026-11-14 · source
New observation reported: We speculate for the first time that the GGNBP2 gene may affect the development of the female reproductive sys…
A source describes a new or expanded observation: “We speculate for the first time that the GGNBP2 gene may affect the development of the female reproductive system.”
“We speculate for the first time that the GGNBP2 gene may affect the development of the female reproductive system.”corroboration 1 · confidence 97% · updated 2026-11-14 · source
New observation reported: In addition, cardiac abnormalities were the first reported prenatal phenotype in 17q12 duplication fetuses…
A source describes a new or expanded observation: “In addition, cardiac abnormalities were the first reported prenatal phenotype in 17q12 duplication fetuses.”
“In addition, cardiac abnormalities were the first reported prenatal phenotype in 17q12 duplication fetuses.”corroboration 1 · confidence 97% · updated 2026-11-14 · source
This entry is version 13. The analytical engine only appends the clearly-labelled “Latest evidence” section; the text above is curated and is not rewritten by the machine. Confidence 80% · last updated 2026-11-14 16:44