Severe microcephaly

Gene: CTU2

The rating of this gene has been updated following NHS Genomic Medicine Service approval.

Created: 10 Mar 2022, 1:37 p.m. | Last Modified: 10 Mar 2022, 1:37 p.m.

Panel Version: 2.292

Comment on list classification: New gene added by Zornitza Stark (Australian Genomics). This gene is associated with a relevant phenotype in OMIM and Gene2Phenotype.

PMID:26633546. Affected members of all 3 families have microcephaly, facial dysmorphia and unilateral renal agenesis. 2/3 families have ambiguous genitalia; however, only 1 family had karyotyping done, which showed normal male karyotype (46 XY). 2/3 had congenital heart disease.

PMID: 27480277. Same variant as PMID:26633546. Affected individuals in this extended family have similar phenotype as PMID:26633546. Patient 1: in addition to microcephaly also has renal anomalies (small kidneys) and possible ambiguous genitalia with normal XY karyotype. Patient 2: cousin of patient 1. In addition to microcephaly did not have renal anomalies and nor ambiguous genitalia. Both patients have congenital heart disease.

PMID: 31301155. 5 new cases, all with microcephaly. 4/5 with renal anomalies, 2/5 with ambiguous genitalia, 4/5 congenital heart disease.

There is enough evidence to support a gene-disease association. This gene should be rated Green at the next review.

Created: 6 May 2021, 10:55 a.m. | Last Modified: 6 May 2021, 10:55 a.m.

Panel Version: 2.146

Green List (high evidence)

Dysmorphic facies, renal agenesis, ambiguous genitalia, microcephaly, polydactyly and lissencephaly (DREAM-PL) as proposed by authors.

PMID: 26633546
- 3 consanguineous families all with the same splice variant (NM_001012762.1:c.873G>A). Assumed to be founder variant
- all had microcephaly but measurements were not provided

PMID: 27480277
- 2 additional patients from an extended consanguineous family with the same variant as above
- Patient 1: head circumference of -3.5SD at birth, not growing
- Patient 2: head circumference of -4.3 SD

PMID: 31301155
- 5 new patients with microcephaly (no measurements provided)
- 3x PTVs and 1x missense
Sources: Expert list

Created: 4 Sep 2020, 10:20 a.m.

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Microcephaly, facial dysmorphism, renal agenesis, and ambiguous genitalia syndrome (MIM#618142)

Publications

• 26633546

Variants in this GENE are reported as part of current diagnostic practice