Table 2

Summary of the clinical signs presented by male patients having a mutation in the MECP2 gene

Mutation	Mic	Res	Reg	Ste	Sco	Age	MR	Other clinical details	Ref
Age, age at last evaluation; Mi, mild; Mic, microcephaly; Mo, moderate; MR, degree of mental retardation; Reg, regression; Res, respiratory dysfunction; S, severe; Sco, scoliosis; SNE, severe neonatal encephalopathy; Ste, stereotypies; U, not present in all patients of a series.
Missense mutations
R133C	Yes	Yes	Yes	Yes	Yes	11 years	S	Rigidity of four limbs, dystonic posture, early convulsions	Geerdink et al¹⁰
S134C	Yes	Yes	Yes	Yes	Yes	10 years	S	Axial and peripheral hypotonia, rigidity of four limbs, seizures	Budden et al¹¹
E137G	U		No		U	21–56 years	Mi to S	No neonatal hypotonia, speech handicap (U)	Gendrot et al⁴¹
A140V	No		No			27–40 years	S	Resting tremor, slow movements	Orrico et al¹³
A140V							Mi to S	No details given	Couvert et al¹²
A140V	No		No		U	11–41 years	Mo to S	Psychosis, pyramidal signs, macro-orchidism, short stature (U)	Lindsay S et al⁴²
F157I	Yes	Yes				25 months	SNE	Limb rigitity, axial hypotonia, movement disorder, head growth deceleration	Kankirawatana et al¹⁵
T158M		Yes				9–11 months	SNE	Pepper and salt hair	Villard et al¹⁶
T158M	Yes	Yes	Yes		Yes	14 months	SNE	Limb spasticity, choreiform movements	Lynch et al¹⁷
R167W	Yes		No			17–55 years	Mi	Four cases, obesity, poor motor coordination, resting tremor	Couvert et al¹²
P225L	No	Yes			Yes	21 years	S	Abnormal temperature control, spastic tetraplegia, dystonia, epilepsy until 7 years	Moog et al¹⁸
P322S	No				Yes	6 years	Mo	Adiposity, uncontrolled seizures, hypotonia, lower limb weakness, intention tremor, ataxia	Ventura et al¹⁹
R344W								Rett-like phenotype (no details given)	Laccone et al²⁰
P405L	No	No	No	Yes	No	29 years	S	No spasticity, can walk, generalised epilepsy	Moog et al²¹
K417M	Yes	Yes				14 months		Head growth deceleration, movement disorder	Kankirawatana et al¹⁵
R453Q								No details given	Couvert et al¹²
In-frame deletions
P387del80			No			24–55 years	Mi to S	No tremor	Gomot et al⁴³
Frameshifts and nonsense mutations
G163fs	Yes	Yes				13 months	SNE	Pepper and salt hair, limb rigidity, seizures	Geerdin et al²³
G252fs	Yes	Yes		Yes		17 months	SNE	Severe hypotonia, recurrent infections	Zeev et al²⁴
G269fs	Yes	Yes				9 months	SNE	Axial hypotonia, severe gastro-oesophageal reflux, intermittent tremor	Schanen et al⁸
G269fs	Yes	Yes	Yes			28 months	SNE	Uncontrolled seizures, axial hypotonia, limb rigidity	Leuzzi et al²⁵
G269fs	Yes	Yes		Yes		27 months	SNE	No limb rigidity, axial hypotonia, movement disorder	Kankirawatana et al¹⁵
R270fs	Yes	Yes				14 months	SNE	Axial hypotonia, no limb rigidity	Kankirawatana et al¹⁵
G273fs	Yes		Yes		Yes	11 years	S	Ataxia, spasticity, uncontrolled seizures	Lugtenberg et al²⁶
L386fs	Yes		Yes	Yes	No	4 years	S	Intention tremor, axial hypotonia, seizures	Dayer et al²⁷
Q406X	No	Yes				34 years	S	Ataxia, spasticity, convulsions, macrocephaly, death at 39 from pneumonia, recurrent infections	Meloni et al²⁸
E472fs	Yes	Yes				10 years	Mo	Obesity, gynaecomastia, hypotonia	Kleefstra et al²⁹
Large duplications
430 kb	No	No	Yes	Yes	No	8 years	S	Uncontrolled generalised epilepsy, no spasticity	Meins et al³⁰
0.4–0.8 Mb	U	Yes				3–35 years	S	Recurrent infections, early death (U), progressive spasticity, axial hypotonia (U), seizures (U)	Van Esch et al³¹
0.4–0.8 Mb	U	Yes				3–25 years	S	Recurrent infections, early death (U), neonatal hypotonia, childhood spasticity, seizures (U)	Friez et al³²
0.2–2.2 Mb	U	No		U		3 months–16 years		Recurrent infections (U), axial hypotonia, childhood spasticity, genital abnormalities (U)	Del Gaudio et al³³
Abnormal karyotypes
Y141X/XXY			Yes	Yes		5.5 years	S	Hypotonia	Schwartzman et al³⁴
T158M/XXY	No		Yes	Yes	Yes	9 years	S	A brother with del22q11	Leonard et al³⁵
E455X/XX	Yes		Yes			2 years	S	SRY translocated on one X chromosome	Maiwald et al³⁶
Somatic mosaicism
P56fs	No	Yes	Yes	No	Yes	6 years	S	Seizures, truncal hypotonia, ataxic gait	Clayton-Smith et al³⁷
R133H						14 years	S	Typical RTT phenotype (no details given)	Armstrong et al³⁸
T158M	Yes		Yes	Yes	Yes	11 years	S	Convulsions and diffuse EEG abnormalities	Kleefstra et al³⁹
R270X	Yes	No	Yes	Yes	Yes	12 years	S	Poor lower limb musculature, hypertonia	Topcu et al⁴⁰