CHMCHMRab escort protein
Autism Reports / Total Reports
8 / 8Rare Variants / Common Variants
13 / 0Aliases
CHM, DXS540, GGTA, HSD-32, REP-1, TCDAssociated Syndromes
-Chromosome Band
Xq21.2Associated Disorders
-Relevance to Autism
A de novo splice-site variant in the CHM gene was identified in an ASD proband from (Yuen et al., 2017), while rare de novo non-coding variants in this gene have been identified in ASD probands from multiple studies (Michaelson et al., 2012; Turner et al., 2016; Yuen et al., 2017; Turner et al., 2017). More recently, a maternally-inherited missense variant in CHM was identified in a male ASD proband from a cohort of 100 Vietnamese children with ASD (Tran et al., 2020).
Molecular Function
This gene encodes component A of the RAB geranylgeranyl transferase holoenzyme. In the dimeric holoenzyme, this subunit binds unprenylated Rab GTPases and then presents them to the catalytic Rab GGTase subunit for the geranylgeranyl transfer reaction. Rab GTPases need to be geranylgeranyled on either one or two cysteine residues in their C-terminus to localize to the correct intracellular membrane.
External Links
SFARI Genomic Platforms
Reports related to CHM (8 Reports)
| # | Type | Title | Author, Year | Autism Report | Associated Disorders |
|---|---|---|---|---|---|
| 1 | Support | Whole-genome sequencing in autism identifies hot spots for de novo germline mutation | Michaelson JJ et al. (2012) | Yes | - |
| 2 | Support | Genome Sequencing of Autism-Affected Families Reveals Disruption of Putative Noncoding Regulatory DNA | Turner TN et al. (2016) | Yes | - |
| 3 | Primary | Whole genome sequencing resource identifies 18 new candidate genes for autism spectrum disorder | C Yuen RK et al. (2017) | Yes | - |
| 4 | Support | Genomic Patterns of De Novo Mutation in Simplex Autism | Turner TN et al. (2017) | Yes | - |
| 5 | Support | Genetic landscape of autism spectrum disorder in Vietnamese children | Tran KT et al. (2020) | Yes | - |
| 6 | Support | A recurrent PJA1 variant in trigonocephaly and neurodevelopmental disorders | Suzuki T et al. (2020) | Yes | - |
| 7 | Support | - | Zhou X et al. (2022) | Yes | - |
| 8 | Support | - | Yasser Al-Sarraj et al. (2024) | Yes | - |
Rare Variants (13)
| Status | Allele Change | Residue Change | Variant Type | Inheritance Pattern | Parental Transmission | Family Type | PubMed ID | Author, Year |
|---|---|---|---|---|---|---|---|---|
| c.190-1G>A | - | splice_site_variant | De novo | - | - | 35982159 | Zhou X et al. (2022) | |
| c.116+13814C>T | - | intron_variant | De novo | - | Simplex | 26749308 | Turner TN et al. (2016) | |
| c.1166+1308A>T | - | intron_variant | De novo | - | Simplex | 28263302 | C Yuen RK et al. (2017) | |
| c.1167-1458A>T | - | intron_variant | De novo | - | Simplex | 28965761 | Turner TN et al. (2017) | |
| c.190-1G>A | - | splice_site_variant | De novo | - | Simplex | 28263302 | C Yuen RK et al. (2017) | |
| c.702+1347G>T | - | intron_variant | De novo | - | Multiplex | 28263302 | C Yuen RK et al. (2017) | |
| c.1510+2813C>T | - | intron_variant | De novo | - | Multiplex | 28263302 | C Yuen RK et al. (2017) | |
| c.1167-1998_1167-1988del | - | intron_variant | De novo | - | Multiplex | 28263302 | C Yuen RK et al. (2017) | |
| c.38T>C | p.Val13Ala | missense_variant | De novo | - | Unknown | 38572415 | Yasser Al-Sarraj et al. (2024) | |
| c.866T>C | p.Met289Thr | missense_variant | Familial | Maternal | Simplex | 32193494 | Tran KT et al. (2020) | |
| c.1167-22212_1167-22208del | - | intron_variant | De novo | - | Multiplex | 28263302 | C Yuen RK et al. (2017) | |
| c.1308C>A | p.Asp436Glu | missense_variant | Familial | Maternal | Multiplex | 32530565 | Suzuki T et al. (2020) | |
| c.117-11055C>T | - | intron_variant | De novo | - | Multiplex (monozygotic twins) | 23260136 | Michaelson JJ et al. (2012) |
Common Variants
No common variants reported.
SFARI Gene score
3
Suggestive Evidence
Score Delta: Score remained at 3
criteria met
See SFARI Gene'scoring criteriaThe literature is replete with relatively small studies of candidate genes, using either common or rare variant approaches, which do not reach the criteria set out for categories 1 and 2. Genes that had two such lines of supporting evidence were placed in category 3, and those with one line of evidence were placed in category 4. Some additional lines of "accessory evidence" (indicated as "acc" in the score cards) could also boost a gene from category 4 to 3.
4/1/2022
3
Increased from to 3
Krishnan Probability Score
Score 0.44807175216014
Ranking 11777/25841 scored genes
[Show Scoring Methodology]
Krishnan and colleagues generated probability scores genome-wide by using a machine learning
approach on a human brain-specific gene network. The method was first presented in Nat
Neurosci 19, 1454-1462 (2016), and scores for more than 25,000 RefSeq genes can be accessed
in column G of supplementary table 3 (see:
http://www.nature.com/neuro/journal/v19/n11/extref/nn.4353-S5.xlsx). A searchable browser,
with the ability to view networks of associated ASD risk genes, can be found at
asd.princeton.edu.
ExAC Score
Score 0.99785101410527
Ranking 1274/18225 scored genes
[Show Scoring Methodology]
The Exome Aggregation Consortium (ExAC) is a summary database of 60,706 exomes that has
been widely used to estimate 'constraint' on mutation for individual genes. It was introduced by
Lek et al. Nature 536, 285-291 (2016), and the ExAC browser can be found at
exac.broadinstitute.org. The pLI score was developed as measure of intolerance to loss-of-
function mutation. A pLI > 0.9 is generally viewed as highly constrained, and thus any loss-of-
function mutations in autism in such a gene would be more likely to confer risk. For a full list of
pLI scores see:
ftp://ftp.broadinstitute.org/pub/ExAC_release/release0.3.1/functional_gene_constraint/fordist_cle
aned_exac_nonTCGA_z_pli_rec_null_data.txt
Sanders TADA Score
Score 0.93481283117607
Ranking 12683/18665 scored genes
[Show Scoring Methodology]
The TADA score ('Transmission and De novo Association') was introduced by He et al. PLoS Genet 9(8):e1003671 (2013),
and is a statistic that integrates evidence from both de novo and transmitted mutations.
It forms the basis for the claim of 65 individual genes being strongly associated with autism risk at a false discovery rate of 0.1 (Sanders et al. Neuron 87, 1215-1233
(2015)). The calculated TADA score for 18,665 RefSeq genes can be found in column P of Supplementary Table 6 in the Sanders et al. paper
(the column headed 'tadaFdrAscSscExomeSscAgpSmallDel'), which represents a combined analysis of exome data and small de novo deletions (see www.cell.com/cms/attachment/2038545319/2052606711/mmc7.xlsx).
Zhang D Score
Score 0.5706702358249
Ranking 172/20870 scored genes
[Show Scoring Methodology]
The DAMAGES score (disease-associated mutation analysis using gene expression signatures),
or D score, was developed to combine evidence from de novo loss-of- function mutation with
evidence from cell-type- specific gene expression in the mouse brain (specifically translational
profiles of 24 specific mouse CNS cell types isolated from 6 different brain regions). Genes with
positive D scores are more likely to be associated with autism risk, with higher-confidence genes
having higher D scores. This statistic was first presented by Zhang & Shen (Hum Mutat 38, 204-
215 (2017), and D scores for more than 20,000 RefSeq genes can be found in column M in
supplementary table 2 from that paper.